diff --git a/exercises/functions/functions2.rs b/exercises/functions/functions2.rs
index 5721a17..fd72c3b 100644
--- a/exercises/functions/functions2.rs
+++ b/exercises/functions/functions2.rs
@@ -1,13 +1,12 @@
 // functions2.rs
 // Make me compile! Execute `rustlings hint functions2` for hints :)
 
-// 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/functions/functions3.rs b/exercises/functions/functions3.rs
index ed5f839..c01dbec 100644
--- a/exercises/functions/functions3.rs
+++ b/exercises/functions/functions3.rs
@@ -1,10 +1,9 @@
 // functions3.rs
 // Make me compile! Execute `rustlings hint functions3` for hints :)
 
-// I AM NOT DONE
 
 fn main() {
-    call_me();
+    call_me(5);
 }
 
 fn call_me(num: u32) {
diff --git a/exercises/functions/functions4.rs b/exercises/functions/functions4.rs
index 58637e4..217c8f4 100644
--- a/exercises/functions/functions4.rs
+++ b/exercises/functions/functions4.rs
@@ -4,18 +4,16 @@
 // This store is having a sale where if the price is an even number, you get
 // 10 Rustbucks off, but if it's an odd number, it's 3 Rustbucks off.
 
-// 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
+       return price - 10
     } else {
-        price - 3
+        return price - 3
     }
 }
 
diff --git a/exercises/functions/functions5.rs b/exercises/functions/functions5.rs
index d22aa6c..3f91f34 100644
--- a/exercises/functions/functions5.rs
+++ b/exercises/functions/functions5.rs
@@ -1,7 +1,6 @@
 // functions5.rs
 // Make me compile! Execute `rustlings hint functions5` for hints :)
 
-// I AM NOT DONE
 
 fn main() {
     let answer = square(3);
@@ -9,5 +8,5 @@ fn main() {
 }
 
 fn square(num: i32) -> i32 {
-    num * num;
+    return num * num;
 }