diff --git a/exercises/00_intro/intro1.rs b/exercises/00_intro/intro1.rs
index 5dd18b45..8c52cf2f 100644
--- a/exercises/00_intro/intro1.rs
+++ b/exercises/00_intro/intro1.rs
@@ -13,11 +13,9 @@
 // Execute `rustlings hint intro1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn main() {
     println!("Hello and");
-    println!(r#"       welcome to...                      "#);
+    println!(r#"       Willkommen zu...                      "#);
     println!(r#"                 _   _ _                  "#);
     println!(r#"  _ __ _   _ ___| |_| (_)_ __   __ _ ___  "#);
     println!(r#" | '__| | | / __| __| | | '_ \ / _` / __| "#);
diff --git a/exercises/00_intro/intro2.rs b/exercises/00_intro/intro2.rs
index a28ad3dc..df9ff552 100644
--- a/exercises/00_intro/intro2.rs
+++ b/exercises/00_intro/intro2.rs
@@ -5,8 +5,8 @@
 // Execute `rustlings hint intro2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
 
 fn main() {
-    printline!("Hello there!")
+    println!("Hello {}!", "World");
+    println!("Hallo {}!", String::from("Welt"));
 }
diff --git a/exercises/01_variables/variables1.rs b/exercises/01_variables/variables1.rs
index b3e089a5..98a0cf22 100644
--- a/exercises/01_variables/variables1.rs
+++ b/exercises/01_variables/variables1.rs
@@ -5,9 +5,7 @@
 // Execute `rustlings hint variables1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn main() {
-    x = 5;
+    let x = 5;
     println!("x has the value {}", x);
 }
diff --git a/exercises/01_variables/variables2.rs b/exercises/01_variables/variables2.rs
index e1c23edf..d24ef1bd 100644
--- a/exercises/01_variables/variables2.rs
+++ b/exercises/01_variables/variables2.rs
@@ -3,10 +3,8 @@
 // Execute `rustlings hint variables2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn main() {
-    let x;
+    let x : u32 = 5;
     if x == 10 {
         println!("x is ten!");
     } else {
diff --git a/exercises/01_variables/variables3.rs b/exercises/01_variables/variables3.rs
index 86bed419..c6061edf 100644
--- a/exercises/01_variables/variables3.rs
+++ b/exercises/01_variables/variables3.rs
@@ -3,9 +3,7 @@
 // Execute `rustlings hint variables3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn main() {
-    let x: i32;
+    let x: i32 = 42;
     println!("Number {}", x);
 }
diff --git a/exercises/01_variables/variables4.rs b/exercises/01_variables/variables4.rs
index 5394f394..c75843ea 100644
--- a/exercises/01_variables/variables4.rs
+++ b/exercises/01_variables/variables4.rs
@@ -3,10 +3,8 @@
 // Execute `rustlings hint variables4` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn main() {
-    let x = 3;
+    let mut x = 3;
     println!("Number {}", x);
     x = 5; // don't change this line
     println!("Number {}", x);
diff --git a/exercises/01_variables/variables5.rs b/exercises/01_variables/variables5.rs
index a29b38be..19ce9d66 100644
--- a/exercises/01_variables/variables5.rs
+++ b/exercises/01_variables/variables5.rs
@@ -3,11 +3,9 @@
 // Execute `rustlings hint variables5` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn main() {
     let number = "T-H-R-E-E"; // don't change this line
     println!("Spell a Number : {}", number);
-    number = 3; // don't rename this variable
+    let number = 3; // don't rename this variable
     println!("Number plus two is : {}", number + 2);
 }
diff --git a/exercises/01_variables/variables6.rs b/exercises/01_variables/variables6.rs
index 853183ba..16514da0 100644
--- a/exercises/01_variables/variables6.rs
+++ b/exercises/01_variables/variables6.rs
@@ -3,9 +3,7 @@
 // Execute `rustlings hint variables6` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
-const NUMBER = 3;
+const NUMBER : i32 = 3;
 fn main() {
     println!("Number {}", NUMBER);
 }
diff --git a/exercises/02_functions/functions1.rs b/exercises/02_functions/functions1.rs
index 40ed9a07..766e1740 100644
--- a/exercises/02_functions/functions1.rs
+++ b/exercises/02_functions/functions1.rs
@@ -3,8 +3,10 @@
 // Execute `rustlings hint functions1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn main() {
     call_me();
 }
+
+fn call_me() {
+    println!("Hello, world!");
+}
diff --git a/exercises/02_functions/functions2.rs b/exercises/02_functions/functions2.rs
index 5154f34d..7af8196a 100644
--- a/exercises/02_functions/functions2.rs
+++ b/exercises/02_functions/functions2.rs
@@ -3,13 +3,11 @@
 // Execute `rustlings hint functions2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn main() {
     call_me(3);
 }
 
-fn call_me(num:) {
+fn call_me(num: i32) {
     for i in 0..num {
         println!("Ring! Call number {}", i + 1);
     }
diff --git a/exercises/02_functions/functions3.rs b/exercises/02_functions/functions3.rs
index 74f44d6d..a231a28f 100644
--- a/exercises/02_functions/functions3.rs
+++ b/exercises/02_functions/functions3.rs
@@ -3,10 +3,8 @@
 // Execute `rustlings hint functions3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn main() {
-    call_me();
+    call_me(10);
 }
 
 fn call_me(num: u32) {
diff --git a/exercises/02_functions/functions4.rs b/exercises/02_functions/functions4.rs
index 77c4b2aa..aec6cf35 100644
--- a/exercises/02_functions/functions4.rs
+++ b/exercises/02_functions/functions4.rs
@@ -8,14 +8,12 @@
 // Execute `rustlings hint functions4` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn main() {
     let original_price = 51;
     println!("Your sale price is {}", sale_price(original_price));
 }
 
-fn sale_price(price: i32) -> {
+fn sale_price(price: i32) -> i32 {
     if is_even(price) {
         price - 10
     } else {
diff --git a/exercises/02_functions/functions5.rs b/exercises/02_functions/functions5.rs
index f1b63f48..c51bea9f 100644
--- a/exercises/02_functions/functions5.rs
+++ b/exercises/02_functions/functions5.rs
@@ -3,13 +3,11 @@
 // Execute `rustlings hint functions5` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn main() {
     let answer = square(3);
     println!("The square of 3 is {}", answer);
 }
 
 fn square(num: i32) -> i32 {
-    num * num;
+    num * num
 }
diff --git a/exercises/03_if/if1.rs b/exercises/03_if/if1.rs
index 4734d78f..4d68a5c5 100644
--- a/exercises/03_if/if1.rs
+++ b/exercises/03_if/if1.rs
@@ -2,9 +2,12 @@
 //
 // Execute `rustlings hint if1` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
-
 pub fn bigger(a: i32, b: i32) -> i32 {
+    if a > b {
+        return a;
+    } else {
+        return b;
+    }
     // Complete this function to return the bigger number!
     // Do not use:
     // - another function call
diff --git a/exercises/03_if/if2.rs b/exercises/03_if/if2.rs
index f512f13f..88d3557a 100644
--- a/exercises/03_if/if2.rs
+++ b/exercises/03_if/if2.rs
@@ -5,14 +5,14 @@
 //
 // Execute `rustlings hint if2` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
-
 pub fn foo_if_fizz(fizzish: &str) -> &str {
     if fizzish == "fizz" {
-        "foo"
-    } else {
-        1
+        return "foo"
     }
+    if fizzish == "fuzz" {
+        return "bar"
+    }
+    return "baz"
 }
 
 // No test changes needed!
diff --git a/exercises/03_if/if3.rs b/exercises/03_if/if3.rs
index 16962740..9c99cd86 100644
--- a/exercises/03_if/if3.rs
+++ b/exercises/03_if/if3.rs
@@ -2,17 +2,15 @@
 //
 // Execute `rustlings hint if3` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
-
 pub fn animal_habitat(animal: &str) -> &'static str {
     let identifier = if animal == "crab" {
         1
     } else if animal == "gopher" {
-        2.0
+        2
     } else if animal == "snake" {
         3
     } else {
-        "Unknown"
+        0
     };
 
     // DO NOT CHANGE THIS STATEMENT BELOW
diff --git a/exercises/04_primitive_types/primitive_types1.rs b/exercises/04_primitive_types/primitive_types1.rs
index 36633400..c3af939a 100644
--- a/exercises/04_primitive_types/primitive_types1.rs
+++ b/exercises/04_primitive_types/primitive_types1.rs
@@ -3,8 +3,6 @@
 // Fill in the rest of the line that has code missing! No hints, there's no
 // tricks, just get used to typing these :)
 
-// I AM NOT DONE
-
 fn main() {
     // Booleans (`bool`)
 
@@ -13,7 +11,7 @@ fn main() {
         println!("Good morning!");
     }
 
-    let // Finish the rest of this line like the example! Or make it be false!
+    let is_evening = false; // Finish the rest of this line like the example! Or make it be false!
     if is_evening {
         println!("Good evening!");
     }
diff --git a/exercises/04_primitive_types/primitive_types2.rs b/exercises/04_primitive_types/primitive_types2.rs
index f1616ed3..9925996c 100644
--- a/exercises/04_primitive_types/primitive_types2.rs
+++ b/exercises/04_primitive_types/primitive_types2.rs
@@ -3,8 +3,6 @@
 // Fill in the rest of the line that has code missing! No hints, there's no
 // tricks, just get used to typing these :)
 
-// I AM NOT DONE
-
 fn main() {
     // Characters (`char`)
 
@@ -19,7 +17,7 @@ fn main() {
         println!("Neither alphabetic nor numeric!");
     }
 
-    let // Finish this line like the example! What's your favorite character?
+    let your_character = '+'; // Finish this line like the example! What's your favorite character?
     // Try a letter, try a number, try a special character, try a character
     // from a different language than your own, try an emoji!
     if your_character.is_alphabetic() {
diff --git a/exercises/04_primitive_types/primitive_types3.rs b/exercises/04_primitive_types/primitive_types3.rs
index 8b0de44e..8e4931ad 100644
--- a/exercises/04_primitive_types/primitive_types3.rs
+++ b/exercises/04_primitive_types/primitive_types3.rs
@@ -5,10 +5,8 @@
 // Execute `rustlings hint primitive_types3` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
-
 fn main() {
-    let a = ???
+    let a = [10; 100];
 
     if a.len() >= 100 {
         println!("Wow, that's a big array!");
diff --git a/exercises/04_primitive_types/primitive_types4.rs b/exercises/04_primitive_types/primitive_types4.rs
index d44d8776..be863098 100644
--- a/exercises/04_primitive_types/primitive_types4.rs
+++ b/exercises/04_primitive_types/primitive_types4.rs
@@ -5,13 +5,11 @@
 // Execute `rustlings hint primitive_types4` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
-
 #[test]
 fn slice_out_of_array() {
     let a = [1, 2, 3, 4, 5];
 
-    let nice_slice = ???
+    let nice_slice = &a[1..4];
 
     assert_eq!([2, 3, 4], nice_slice)
 }
diff --git a/exercises/04_primitive_types/primitive_types5.rs b/exercises/04_primitive_types/primitive_types5.rs
index f646986e..7a330445 100644
--- a/exercises/04_primitive_types/primitive_types5.rs
+++ b/exercises/04_primitive_types/primitive_types5.rs
@@ -5,11 +5,9 @@
 // Execute `rustlings hint primitive_types5` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
-
 fn main() {
     let cat = ("Furry McFurson", 3.5);
-    let /* your pattern here */ = cat;
+    let (name, age) = cat;
 
     println!("{} is {} years old.", name, age);
 }
diff --git a/exercises/04_primitive_types/primitive_types6.rs b/exercises/04_primitive_types/primitive_types6.rs
index 07cc46c6..0ed7cfd2 100644
--- a/exercises/04_primitive_types/primitive_types6.rs
+++ b/exercises/04_primitive_types/primitive_types6.rs
@@ -6,13 +6,11 @@
 // Execute `rustlings hint primitive_types6` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
-
 #[test]
 fn indexing_tuple() {
     let numbers = (1, 2, 3);
     // Replace below ??? with the tuple indexing syntax.
-    let second = ???;
+    let second = numbers.1;
 
     assert_eq!(2, second,
         "This is not the 2nd number in the tuple!")
diff --git a/exercises/05_vecs/vecs1.rs b/exercises/05_vecs/vecs1.rs
index 65b7a7f8..2755504b 100644
--- a/exercises/05_vecs/vecs1.rs
+++ b/exercises/05_vecs/vecs1.rs
@@ -7,11 +7,9 @@
 //
 // Execute `rustlings hint vecs1` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
-
 fn array_and_vec() -> ([i32; 4], Vec<i32>) {
     let a = [10, 20, 30, 40]; // a plain array
-    let v = // TODO: declare your vector here with the macro for vectors
+    let v = vec![10,20,30,40]; // TODO: declare your vector here with the macro for vectors
 
     (a, v)
 }
diff --git a/exercises/05_vecs/vecs2.rs b/exercises/05_vecs/vecs2.rs
index e92c970a..31518d59 100644
--- a/exercises/05_vecs/vecs2.rs
+++ b/exercises/05_vecs/vecs2.rs
@@ -7,13 +7,11 @@
 //
 // Execute `rustlings hint vecs2` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
-
 fn vec_loop(mut v: Vec<i32>) -> Vec<i32> {
     for element in v.iter_mut() {
         // TODO: Fill this up so that each element in the Vec `v` is
         // multiplied by 2.
-        ???
+        *element = *element * 2;
     }
 
     // At this point, `v` should be equal to [4, 8, 12, 16, 20].
@@ -23,8 +21,7 @@ fn vec_loop(mut v: Vec<i32>) -> Vec<i32> {
 fn vec_map(v: &Vec<i32>) -> Vec<i32> {
     v.iter().map(|element| {
         // TODO: Do the same thing as above - but instead of mutating the
-        // Vec, you can just return the new number!
-        ???
+        element * 2 // Vec, you can just return the new number!
     }).collect()
 }
 
diff --git a/exercises/06_move_semantics/move_semantics1.rs b/exercises/06_move_semantics/move_semantics1.rs
index e0639375..29485b50 100644
--- a/exercises/06_move_semantics/move_semantics1.rs
+++ b/exercises/06_move_semantics/move_semantics1.rs
@@ -3,19 +3,17 @@
 // Execute `rustlings hint move_semantics1` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
-
 #[test]
 fn main() {
     let vec0 = vec![22, 44, 66];
 
-    let vec1 = fill_vec(vec0);
+    let mut vec1 = fill_vec(vec0);
 
     assert_eq!(vec1, vec![22, 44, 66, 88]);
 }
 
 fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
-    let vec = vec;
+    let mut vec = vec;
 
     vec.push(88);
 
diff --git a/exercises/06_move_semantics/move_semantics2.rs b/exercises/06_move_semantics/move_semantics2.rs
index baf6bcc9..e3c0402f 100644
--- a/exercises/06_move_semantics/move_semantics2.rs
+++ b/exercises/06_move_semantics/move_semantics2.rs
@@ -5,13 +5,11 @@
 // Execute `rustlings hint move_semantics2` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
-
 #[test]
 fn main() {
     let vec0 = vec![22, 44, 66];
 
-    let mut vec1 = fill_vec(vec0);
+    let mut vec1 = fill_vec(vec0.clone());
 
     assert_eq!(vec0, vec![22, 44, 66]);
     assert_eq!(vec1, vec![22, 44, 66, 88]);
diff --git a/exercises/06_move_semantics/move_semantics3.rs b/exercises/06_move_semantics/move_semantics3.rs
index 7af9e694..d473bb68 100644
--- a/exercises/06_move_semantics/move_semantics3.rs
+++ b/exercises/06_move_semantics/move_semantics3.rs
@@ -6,8 +6,6 @@
 // Execute `rustlings hint move_semantics3` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
-
 #[test]
 fn main() {
     let vec0 = vec![22, 44, 66];
@@ -17,7 +15,7 @@ fn main() {
     assert_eq!(vec1, vec![22, 44, 66, 88]);
 }
 
-fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
+fn fill_vec(mut vec: Vec<i32>) -> Vec<i32> {
     vec.push(88);
 
     vec
diff --git a/exercises/06_move_semantics/move_semantics4.rs b/exercises/06_move_semantics/move_semantics4.rs
index 80b49dba..c0ac9c26 100644
--- a/exercises/06_move_semantics/move_semantics4.rs
+++ b/exercises/06_move_semantics/move_semantics4.rs
@@ -7,13 +7,11 @@
 // Execute `rustlings hint move_semantics4` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
-
 #[test]
 fn main() {
-    let vec0 = vec![22, 44, 66];
+   // let vec0 = vec![22, 44, 66];
 
-    let mut vec1 = fill_vec(vec0);
+    let mut vec1 = fill_vec();
 
     assert_eq!(vec1, vec![22, 44, 66, 88]);
 }
@@ -21,8 +19,11 @@ fn main() {
 // `fill_vec()` no longer takes `vec: Vec<i32>` as argument - don't change this!
 fn fill_vec() -> Vec<i32> {
     // Instead, let's create and fill the Vec in here - how do you do that?
-    let mut vec = vec;
+    let mut vec = Vec::new();
 
+    vec.push(22);
+    vec.push(44);
+    vec.push(66);
     vec.push(88);
 
     vec
diff --git a/exercises/06_move_semantics/move_semantics5.rs b/exercises/06_move_semantics/move_semantics5.rs
index 267bdccc..bf373822 100644
--- a/exercises/06_move_semantics/move_semantics5.rs
+++ b/exercises/06_move_semantics/move_semantics5.rs
@@ -6,14 +6,11 @@
 // Execute `rustlings hint move_semantics5` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
-
-#[test]
 fn main() {
     let mut x = 100;
     let y = &mut x;
-    let z = &mut x;
     *y += 100;
+    let z = &mut x;
     *z += 1000;
     assert_eq!(x, 1200);
 }
diff --git a/exercises/06_move_semantics/move_semantics6.rs b/exercises/06_move_semantics/move_semantics6.rs
index cace4ca6..29be761b 100644
--- a/exercises/06_move_semantics/move_semantics6.rs
+++ b/exercises/06_move_semantics/move_semantics6.rs
@@ -5,12 +5,10 @@
 // Execute `rustlings hint move_semantics6` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
-
 fn main() {
     let data = "Rust is great!".to_string();
 
-    get_char(data);
+    get_char(data.clone());
 
     string_uppercase(&data);
 }
@@ -22,7 +20,7 @@ fn get_char(data: String) -> char {
 
 // Should take ownership
 fn string_uppercase(mut data: &String) {
-    data = &data.to_uppercase();
+    let tmp = &data.to_uppercase();
 
-    println!("{}", data);
+    println!("{}", tmp);
 }
diff --git a/exercises/07_structs/structs1.rs b/exercises/07_structs/structs1.rs
index 5fa5821c..06205918 100644
--- a/exercises/07_structs/structs1.rs
+++ b/exercises/07_structs/structs1.rs
@@ -5,13 +5,13 @@
 // Execute `rustlings hint structs1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 struct ColorClassicStruct {
-    // TODO: Something goes here
+    red: u8,
+    green: u8,
+    blue: u8
 }
 
-struct ColorTupleStruct(/* TODO: Something goes here */);
+struct ColorTupleStruct(u8,u8,u8);
 
 #[derive(Debug)]
 struct UnitLikeStruct;
@@ -23,7 +23,7 @@ mod tests {
     #[test]
     fn classic_c_structs() {
         // TODO: Instantiate a classic c struct!
-        // let green =
+        let green = ColorClassicStruct{red: 0, green: 255, blue: 0 };
 
         assert_eq!(green.red, 0);
         assert_eq!(green.green, 255);
@@ -33,7 +33,7 @@ mod tests {
     #[test]
     fn tuple_structs() {
         // TODO: Instantiate a tuple struct!
-        // let green =
+        let green = ColorTupleStruct(0,255,0);
 
         assert_eq!(green.0, 0);
         assert_eq!(green.1, 255);
@@ -43,7 +43,7 @@ mod tests {
     #[test]
     fn unit_structs() {
         // TODO: Instantiate a unit-like struct!
-        // let unit_like_struct =
+        let unit_like_struct = UnitLikeStruct;
         let message = format!("{:?}s are fun!", unit_like_struct);
 
         assert_eq!(message, "UnitLikeStructs are fun!");
diff --git a/exercises/07_structs/structs2.rs b/exercises/07_structs/structs2.rs
index 328567f0..f338033e 100644
--- a/exercises/07_structs/structs2.rs
+++ b/exercises/07_structs/structs2.rs
@@ -5,8 +5,6 @@
 // Execute `rustlings hint structs2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 #[derive(Debug)]
 struct Order {
     name: String,
@@ -38,7 +36,7 @@ mod tests {
     fn your_order() {
         let order_template = create_order_template();
         // TODO: Create your own order using the update syntax and template above!
-        // let your_order =
+        let your_order = Order {  name: String::from("Hacker in Rust"), count: 1, ..order_template };
         assert_eq!(your_order.name, "Hacker in Rust");
         assert_eq!(your_order.year, order_template.year);
         assert_eq!(your_order.made_by_phone, order_template.made_by_phone);
diff --git a/exercises/07_structs/structs3.rs b/exercises/07_structs/structs3.rs
index 7cda5af1..82e0fbc6 100644
--- a/exercises/07_structs/structs3.rs
+++ b/exercises/07_structs/structs3.rs
@@ -1,27 +1,20 @@
 // structs3.rs
-//
 // Structs contain data, but can also have logic. In this exercise we have
 // defined the Package struct and we want to test some logic attached to it.
 // Make the code compile and the tests pass!
-//
-// Execute `rustlings hint structs3` or use the `hint` watch subcommand for a
-// hint.
-
-// I AM NOT DONE
+// Execute `rustlings hint structs3` or use the `hint` watch subcommand for a hint.
 
 #[derive(Debug)]
 struct Package {
     sender_country: String,
     recipient_country: String,
-    weight_in_grams: u32,
+    weight_in_grams: i32,
 }
 
 impl Package {
-    fn new(sender_country: String, recipient_country: String, weight_in_grams: u32) -> Package {
-        if weight_in_grams < 10 {
-            // This is not how you should handle errors in Rust,
-            // but we will learn about error handling later.
-            panic!("Can not ship a package with weight below 10 grams.")
+    fn new(sender_country: String, recipient_country: String, weight_in_grams: i32) -> Package {
+        if weight_in_grams <= 0 {
+            panic!("Can not ship a weightless package.")
         } else {
             Package {
                 sender_country,
@@ -31,12 +24,12 @@ impl Package {
         }
     }
 
-    fn is_international(&self) -> ??? {
-        // Something goes here...
+    fn is_international(&self) -> bool {
+        !self.sender_country.eq(&self.recipient_country)
     }
 
-    fn get_fees(&self, cents_per_gram: u32) -> ??? {
-        // Something goes here...
+    fn get_fees(&self, cents_per_gram: i32) -> i32 {
+        self.weight_in_grams * cents_per_gram
     }
 }
 
@@ -50,7 +43,7 @@ mod tests {
         let sender_country = String::from("Spain");
         let recipient_country = String::from("Austria");
 
-        Package::new(sender_country, recipient_country, 5);
+        Package::new(sender_country, recipient_country, -2210);
     }
 
     #[test]
diff --git a/exercises/08_enums/enums1.rs b/exercises/08_enums/enums1.rs
index 25525b25..046ddd92 100644
--- a/exercises/08_enums/enums1.rs
+++ b/exercises/08_enums/enums1.rs
@@ -2,11 +2,12 @@
 //
 // No hints this time! ;)
 
-// I AM NOT DONE
-
 #[derive(Debug)]
 enum Message {
-    // TODO: define a few types of messages as used below
+    Quit,
+    Echo,
+    Move,
+    ChangeColor
 }
 
 fn main() {
diff --git a/exercises/08_enums/enums2.rs b/exercises/08_enums/enums2.rs
index df93fe0f..e0833ee6 100644
--- a/exercises/08_enums/enums2.rs
+++ b/exercises/08_enums/enums2.rs
@@ -3,11 +3,12 @@
 // Execute `rustlings hint enums2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 #[derive(Debug)]
 enum Message {
-    // TODO: define the different variants used below
+    Move{x: i32, y: i32},
+    Echo(String),
+    ChangeColor(i32,i32,i32),
+    Quit
 }
 
 impl Message {
diff --git a/exercises/08_enums/enums3.rs b/exercises/08_enums/enums3.rs
index 92d18c46..83845f8e 100644
--- a/exercises/08_enums/enums3.rs
+++ b/exercises/08_enums/enums3.rs
@@ -1,14 +1,12 @@
 // enums3.rs
-//
 // Address all the TODOs to make the tests pass!
-//
-// Execute `rustlings hint enums3` or use the `hint` watch subcommand for a
-// hint.
-
-// I AM NOT DONE
+// Execute `rustlings hint enums3` or use the `hint` watch subcommand for a hint.
 
 enum Message {
-    // TODO: implement the message variant types based on their usage below
+    ChangeColor(u8, u8, u8),
+    Echo(String),
+    Move(Point),
+    Quit
 }
 
 struct Point {
@@ -20,7 +18,6 @@ struct State {
     color: (u8, u8, u8),
     position: Point,
     quit: bool,
-    message: String,
 }
 
 impl State {
@@ -32,8 +29,8 @@ impl State {
         self.quit = true;
     }
 
-    fn echo(&mut self, s: String) {
-        self.message = s
+    fn echo(&self, s: String) {
+        println!("{}", s);
     }
 
     fn move_position(&mut self, p: Point) {
@@ -42,8 +39,13 @@ impl State {
 
     fn process(&mut self, message: Message) {
         // TODO: create a match expression to process the different message variants
-        // Remember: When passing a tuple as a function argument, you'll need extra parentheses:
-        // fn function((t, u, p, l, e))
+        // Remember: When passing a tuple as a function argument, you'll need extra parentheses: fn function((t, u, p, l, e))
+    match message {
+        Message::ChangeColor(r,g,b) => self.change_color((r,g,b)),
+        Message::Echo(text) => self.echo(text),
+        Message::Move(point) => self.move_position(point),
+        Message::Quit => self.quit()
+    }
     }
 }
 
@@ -57,10 +59,9 @@ mod tests {
             quit: false,
             position: Point { x: 0, y: 0 },
             color: (0, 0, 0),
-            message: "hello world".to_string(),
         };
         state.process(Message::ChangeColor(255, 0, 255));
-        state.process(Message::Echo(String::from("Hello world!")));
+        state.process(Message::Echo(String::from("hello world")));
         state.process(Message::Move(Point { x: 10, y: 15 }));
         state.process(Message::Quit);
 
@@ -68,6 +69,5 @@ mod tests {
         assert_eq!(state.position.x, 10);
         assert_eq!(state.position.y, 15);
         assert_eq!(state.quit, true);
-        assert_eq!(state.message, "Hello world!");
     }
 }
diff --git a/exercises/09_strings/strings1.rs b/exercises/09_strings/strings1.rs
index f50e1fa9..e789b8f0 100644
--- a/exercises/09_strings/strings1.rs
+++ b/exercises/09_strings/strings1.rs
@@ -5,13 +5,11 @@
 // Execute `rustlings hint strings1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn main() {
     let answer = current_favorite_color();
     println!("My current favorite color is {}", answer);
 }
 
 fn current_favorite_color() -> String {
-    "blue"
+    "blue".to_string()
 }
diff --git a/exercises/09_strings/strings2.rs b/exercises/09_strings/strings2.rs
index 4d95d16a..ca16ea3d 100644
--- a/exercises/09_strings/strings2.rs
+++ b/exercises/09_strings/strings2.rs
@@ -5,11 +5,9 @@
 // Execute `rustlings hint strings2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn main() {
     let word = String::from("green"); // Try not changing this line :)
-    if is_a_color_word(word) {
+    if is_a_color_word(&word) {
         println!("That is a color word I know!");
     } else {
         println!("That is not a color word I know.");
diff --git a/exercises/09_strings/strings3.rs b/exercises/09_strings/strings3.rs
index b29f9325..ea34b085 100644
--- a/exercises/09_strings/strings3.rs
+++ b/exercises/09_strings/strings3.rs
@@ -3,21 +3,19 @@
 // Execute `rustlings hint strings3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 fn trim_me(input: &str) -> String {
     // TODO: Remove whitespace from both ends of a string!
-    ???
+    input.trim().to_string()
 }
 
 fn compose_me(input: &str) -> String {
     // TODO: Add " world!" to the string! There's multiple ways to do this!
-    ???
+    input.to_owned() + " world!"
 }
 
 fn replace_me(input: &str) -> String {
     // TODO: Replace "cars" in the string with "balloons"!
-    ???
+    input.replace("cars", "balloons")
 }
 
 #[cfg(test)]
diff --git a/exercises/09_strings/strings4.rs b/exercises/09_strings/strings4.rs
index e8c54acc..999ba803 100644
--- a/exercises/09_strings/strings4.rs
+++ b/exercises/09_strings/strings4.rs
@@ -7,8 +7,6 @@
 //
 // No hints this time!
 
-// I AM NOT DONE
-
 fn string_slice(arg: &str) {
     println!("{}", arg);
 }
@@ -17,14 +15,14 @@ fn string(arg: String) {
 }
 
 fn main() {
-    ???("blue");
-    ???("red".to_string());
-    ???(String::from("hi"));
-    ???("rust is fun!".to_owned());
-    ???("nice weather".into());
-    ???(format!("Interpolation {}", "Station"));
-    ???(&String::from("abc")[0..1]);
-    ???("  hello there ".trim());
-    ???("Happy Monday!".to_string().replace("Mon", "Tues"));
-    ???("mY sHiFt KeY iS sTiCkY".to_lowercase());
+    string_slice("blue");
+    string("red".to_string());
+    string(String::from("hi"));
+    string("rust is fun!".to_owned());
+    string_slice("nice weather".into());
+    string(format!("Interpolation {}", "Station"));
+    string_slice(&String::from("abc")[0..1]);
+    string_slice("  hello there ".trim());
+    string("Happy Monday!".to_string().replace("Mon", "Tues"));
+    string("mY sHiFt KeY iS sTiCkY".to_lowercase());
 }
diff --git a/exercises/10_modules/modules1.rs b/exercises/10_modules/modules1.rs
index 9eb5a48b..a26f5c45 100644
--- a/exercises/10_modules/modules1.rs
+++ b/exercises/10_modules/modules1.rs
@@ -3,15 +3,13 @@
 // Execute `rustlings hint modules1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 mod sausage_factory {
     // Don't let anybody outside of this module see this!
     fn get_secret_recipe() -> String {
         String::from("Ginger")
     }
 
-    fn make_sausage() {
+    pub fn make_sausage() {
         get_secret_recipe();
         println!("sausage!");
     }
diff --git a/exercises/10_modules/modules2.rs b/exercises/10_modules/modules2.rs
index 04154543..505e422b 100644
--- a/exercises/10_modules/modules2.rs
+++ b/exercises/10_modules/modules2.rs
@@ -7,12 +7,9 @@
 // Execute `rustlings hint modules2` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
-mod delicious_snacks {
-    // TODO: Fix these use statements
-    use self::fruits::PEAR as ???
-    use self::veggies::CUCUMBER as ???
+pub mod delicious_snacks {
+    pub use self::fruits::PEAR as fruit;
+    pub use self::veggies::CUCUMBER as veggie;
 
     mod fruits {
         pub const PEAR: &'static str = "Pear";
diff --git a/exercises/10_modules/modules3.rs b/exercises/10_modules/modules3.rs
index f2bb0503..7693b823 100644
--- a/exercises/10_modules/modules3.rs
+++ b/exercises/10_modules/modules3.rs
@@ -8,10 +8,8 @@
 // Execute `rustlings hint modules3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 // TODO: Complete this use statement
-use ???
+use std::time::*;
 
 fn main() {
     match SystemTime::now().duration_since(UNIX_EPOCH) {
diff --git a/exercises/11_hashmaps/hashmaps1.rs b/exercises/11_hashmaps/hashmaps1.rs
index 80829eaa..2185577b 100644
--- a/exercises/11_hashmaps/hashmaps1.rs
+++ b/exercises/11_hashmaps/hashmaps1.rs
@@ -11,18 +11,19 @@
 // Execute `rustlings hint hashmaps1` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 use std::collections::HashMap;
 
 fn fruit_basket() -> HashMap<String, u32> {
-    let mut basket = // TODO: declare your hash map here.
+    let mut basket = HashMap::new(); // TODO: declare your hash map here.
 
     // Two bananas are already given for you :)
     basket.insert(String::from("banana"), 2);
 
     // TODO: Put more fruits in your basket here.
 
+    basket.insert(String::from("apple"), 3);
+    basket.insert(String::from("orange"), 3);
+
     basket
 }
 
diff --git a/exercises/11_hashmaps/hashmaps2.rs b/exercises/11_hashmaps/hashmaps2.rs
index a5925690..ff067948 100644
--- a/exercises/11_hashmaps/hashmaps2.rs
+++ b/exercises/11_hashmaps/hashmaps2.rs
@@ -1,24 +1,21 @@
 // hashmaps2.rs
-//
-// We're collecting different fruits to bake a delicious fruit cake. For this,
-// we have a basket, which we'll represent in the form of a hash map. The key
-// represents the name of each fruit we collect and the value represents how
-// many of that particular fruit we have collected. Three types of fruits -
-// Apple (4), Mango (2) and Lychee (5) are already in the basket hash map. You
-// must add fruit to the basket so that there is at least one of each kind and
-// more than 11 in total - we have a lot of mouths to feed. You are not allowed
-// to insert any more of these fruits!
+// We're collecting different fruits to bake a delicious fruit cake.
+// For this, we have a basket, which we'll represent in the form of a hash
+// map. The key represents the name of each fruit we collect and the value
+// represents how many of that particular fruit we have collected.
+// Three types of fruits - Apple (4), Mango (2) and Lychee (5) are already
+// in the basket hash map.
+// You must add fruit to the basket so that there is at least
+// one of each kind and more than 11 in total - we have a lot of mouths to feed.
+// You are not allowed to insert any more of these fruits!
 //
 // Make me pass the tests!
 //
-// Execute `rustlings hint hashmaps2` or use the `hint` watch subcommand for a
-// hint.
-
-// I AM NOT DONE
+// Execute `rustlings hint hashmaps2` or use the `hint` watch subcommand for a hint.
 
 use std::collections::HashMap;
 
-#[derive(Hash, PartialEq, Eq)]
+#[derive(Hash, PartialEq, Eq, Debug)]
 enum Fruit {
     Apple,
     Banana,
@@ -37,10 +34,31 @@ fn fruit_basket(basket: &mut HashMap<Fruit, u32>) {
     ];
 
     for fruit in fruit_kinds {
-        // TODO: Insert new fruits if they are not already present in the
-        // basket. Note that you are not allowed to put any type of fruit that's
-        // already present!
+        if basket.get(&fruit).is_none() {
+            basket.insert(fruit, 1);
+        }
+
+        // TODO: Insert new fruits if they are not already present in the basket.
+        // Note that you are not allowed to put any type of fruit that's already
+        // present!
     }
+    println!("Content");
+    for fruit in basket {
+        println!("Fruit {:?} {}", fruit.0, fruit.1)
+    }
+}
+
+fn get_fruit_basket() -> HashMap<Fruit, u32> {
+    let mut basket = HashMap::<Fruit, u32>::new();
+    basket.insert(Fruit::Apple, 4);
+    basket.insert(Fruit::Mango, 2);
+    basket.insert(Fruit::Lychee, 5);
+
+    basket
+}
+
+fn main() {
+    fruit_basket(&mut get_fruit_basket());
 }
 
 #[cfg(test)]
@@ -81,13 +99,4 @@ mod tests {
         let count = basket.values().sum::<u32>();
         assert!(count > 11);
     }
-    
-    #[test]
-    fn all_fruit_types_in_basket() {
-        let mut basket = get_fruit_basket();
-        fruit_basket(&mut basket);
-        for amount in basket.values() {
-            assert_ne!(amount, &0);
-        }
-    }
 }
diff --git a/exercises/11_hashmaps/hashmaps3.rs b/exercises/11_hashmaps/hashmaps3.rs
index 08e977c3..bb6a783a 100644
--- a/exercises/11_hashmaps/hashmaps3.rs
+++ b/exercises/11_hashmaps/hashmaps3.rs
@@ -1,3 +1,4 @@
+
 // hashmaps3.rs
 //
 // A list of scores (one per line) of a soccer match is given. Each line is of
@@ -14,12 +15,11 @@
 // Execute `rustlings hint hashmaps3` or use the `hint` watch subcommand for a
 // hint.
 
-// I AM NOT DONE
-
 use std::collections::HashMap;
 
 // A structure to store the goal details of a team.
 struct Team {
+    name: String,
     goals_scored: u8,
     goals_conceded: u8,
 }
@@ -34,11 +34,31 @@ fn build_scores_table(results: String) -> HashMap<String, Team> {
         let team_1_score: u8 = v[2].parse().unwrap();
         let team_2_name = v[1].to_string();
         let team_2_score: u8 = v[3].parse().unwrap();
-        // TODO: Populate the scores table with details extracted from the
-        // current line. Keep in mind that goals scored by team_1
-        // will be the number of goals conceded from team_2, and similarly
-        // goals scored by team_2 will be the number of goals conceded by
-        // team_1.
+
+        scores
+            .entry(team_1_name)
+            .and_modify(|e| {
+                e.goals_scored += team_1_score;
+                e.goals_conceded += team_2_score;
+            })
+            .or_insert_with_key(|name| Team {
+                name: name.to_string(),
+                goals_scored: team_1_score,
+                goals_conceded: team_2_score,
+            });
+
+        scores
+            .entry(team_2_name)
+            .and_modify(|e| {
+                e.goals_scored += team_2_score;
+                e.goals_conceded += team_1_score;
+            })
+            .or_insert_with_key(|name| Team {
+                name: name.to_string(),
+                goals_scored: team_2_score,
+                goals_conceded: team_1_score,
+            });
+
     }
     scores
 }
diff --git a/exercises/12_options/options1.rs b/exercises/12_options/options1.rs
index e131b48b..ead48a2f 100644
--- a/exercises/12_options/options1.rs
+++ b/exercises/12_options/options1.rs
@@ -1,19 +1,20 @@
 // options1.rs
-//
-// Execute `rustlings hint options1` or use the `hint` watch subcommand for a
-// hint.
-
-// I AM NOT DONE
+// Execute `rustlings hint options1` or use the `hint` watch subcommand for a hint.
 
 // This function returns how much icecream there is left in the fridge.
 // If it's before 10PM, there's 5 pieces left. At 10PM, someone eats them
 // all, so there'll be no more left :(
 fn maybe_icecream(time_of_day: u16) -> Option<u16> {
-    // We use the 24-hour system here, so 10PM is a value of 22 and 12AM is a
-    // value of 0 The Option output should gracefully handle cases where
-    // time_of_day > 23.
+    // We use the 24-hour system here, so 10PM is a value of 22 and 12AM is a value of 0
+    // The Option output should gracefully handle cases where time_of_day > 23.
     // TODO: Complete the function body - remember to return an Option!
-    ???
+    if time_of_day < 22 {
+        Some(5)
+    } else if time_of_day < 25 {
+        Some(0)
+    } else {
+        None
+    }
 }
 
 #[cfg(test)]
@@ -31,9 +32,8 @@ mod tests {
 
     #[test]
     fn raw_value() {
-        // TODO: Fix this test. How do you get at the value contained in the
-        // Option?
-        let icecreams = maybe_icecream(12);
+        // TODO: Fix this test. How do you get at the value contained in the Option?
+        let icecreams = maybe_icecream(12).unwrap();
         assert_eq!(icecreams, 5);
     }
 }
diff --git a/exercises/quiz1.rs b/exercises/quiz1.rs
index 4ee5ada7..9e507c90 100644
--- a/exercises/quiz1.rs
+++ b/exercises/quiz1.rs
@@ -13,10 +13,14 @@
 //
 // No hints this time ;)
 
-// I AM NOT DONE
-
 // Put your function here!
-// fn calculate_price_of_apples {
+ fn calculate_price_of_apples(apple_count: i32 ) -> i32 {
+    if apple_count > 40 {
+        apple_count
+    } else {
+        apple_count * 2
+    }
+}
 
 // Don't modify this function!
 #[test]
diff --git a/exercises/quiz2.rs b/exercises/quiz2.rs
index 29925caf..185c8051 100644
--- a/exercises/quiz2.rs
+++ b/exercises/quiz2.rs
@@ -20,8 +20,6 @@
 //
 // No hints this time!
 
-// I AM NOT DONE
-
 pub enum Command {
     Uppercase,
     Trim,
@@ -29,14 +27,20 @@ pub enum Command {
 }
 
 mod my_module {
+    use std::ops::Add;
     use super::Command;
 
     // TODO: Complete the function signature!
-    pub fn transformer(input: ???) -> ??? {
+    pub fn transformer(input: Vec<(String, Command)>) -> Vec<String> {
         // TODO: Complete the output declaration!
-        let mut output: ??? = vec![];
+        let mut output = vec![];
         for (string, command) in input.iter() {
-            // TODO: Complete the function body. You can do it!
+            let result = match command {
+                Command::Uppercase => string.to_uppercase(),
+                Command::Trim => string.trim().into(),
+                Command::Append(times) => string.to_owned() + &"bar".repeat(*times)
+            };
+            output.push(result);
         }
         output
     }
@@ -45,9 +49,8 @@ mod my_module {
 #[cfg(test)]
 mod tests {
     // TODO: What do we need to import to have `transformer` in scope?
-    use ???;
+    use super::my_module::transformer;
     use super::Command;
-
     #[test]
     fn it_works() {
         let output = transformer(vec![