update

exercise/exercises/functions/functions2.rs

@@ -10,6 +10,6 @@ fn main() {
 
 fn call_me(num:) {
     for i in 0..num {
-        println!("Ring! Call number {}", i + 1);
+        println!("Ring! Call number {}", i + 1);// 译："叮！呼叫号码 {}"
     }
 }

exercise/exercises/functions/functions3.rs

@@ -1,8 +1,9 @@
 // functions3.rs
-// Make me compile! Execute `rustlings hint functions3` for hints :)
+// 让我能够编译！执行 `rustex hint functions3` 获取提示 :)
 
 // I AM NOT DONE
 
+/// 翻译: [mg-chao](https://github.com/mg-chao)
 fn main() {
     call_me();
 }

exercise/exercises/functions/functions4.rs

@@ -1,14 +1,15 @@
 // functions4.rs
-// Make me compile! Execute `rustlings hint functions4` for hints :)
+// 让我能够编译！执行 `rustex hint functions4` 获取提示 :)
 
-// This store is having a sale where if the price is an even number, you get
+// 商店正在进行促销，如果价格是偶数，可以优惠 10 Rustbucks，如果是奇数，则优惠 3 Rustbucks。
-// 10 Rustbucks off, but if it's an odd number, it's 3 Rustbucks off.
+// 译：Rustbucks 可能想表达 Rust元 的意思，好比 美元 。
 
 // I AM NOT DONE
 
+/// 翻译: [mg-chao](https://github.com/mg-chao)
 fn main() {
     let original_price = 51;
-    println!("Your sale price is {}", sale_price(original_price));
+    println!("Your sale price is {}", sale_price(original_price));// 译："你需支付 {}"
 }
 
 fn sale_price(price: i32) -> {

exercise/exercises/functions/functions5.rs

@@ -1,11 +1,12 @@
 // functions5.rs
-// Make me compile! Execute `rustlings hint functions5` for hints :)
+// 让我能够编译！执行 `rustex hint functions5` 获取提示 :)
 
 // I AM NOT DONE
 
+/// 翻译: [mg-chao](https://github.com/mg-chao)
 fn main() {
     let answer = square(3);
-    println!("The answer is {}", answer);
+    println!("The answer is {}", answer);// 译："答案是 {}"
 }
 
 fn square(num: i32) -> i32 {

exercise/info.toml

@@ -87,37 +87,35 @@ name = "functions2"
 path = "exercises/functions/functions2.rs"
 mode = "compile"
 hint = """
- Rust 要求函数签名有类型标注，但是 `call_me` 函数缺少 `num` 的类型注明。"""
+ Rust 要求函数签名（signature）有类型标注，但是 `call_me` 函数缺少 `num` 的类型标注。"""
 
 [[exercises]]
 name = "functions3"
 path = "exercises/functions/functions3.rs"
 mode = "compile"
 hint = """
-This time, the function *declaration* is okay, but there's something wrong
+此时, 函数 *声明（declaration）* 是没问题的，但函数调用出了问题"""
-with the place where we're calling the function."""
 
 [[exercises]]
 name = "functions4"
 path = "exercises/functions/functions4.rs"
 mode = "compile"
 hint = """
-The error message points to line 14 and says it expects a type after the
+错误信息指向第 15 行，说希望在`->`之后有一个类型。
-`->`. This is where the function's return type should be-- take a look at
+那个地方标注了函数的返回类型——看看 `is_even` 函数的示例吧"""
-the `is_even` function for an example!"""
 
 [[exercises]]
 name = "functions5"
 path = "exercises/functions/functions5.rs"
 mode = "compile"
 hint = """
-This is a really common error that can be fixed by removing one character.
+这是一个非常常见的错误，可以通过删除一个字符来解决。
-It happens because Rust distinguishes between expressions and statements: expressions return
+发生的原因是 Rust 区分了表达式和语句：表达式根据其运算数（operand）返回一个值, 
-a value based on its operand, and statements simply return a () type which behaves just like `void` in C/C++ language.
+而语句仅返回一个 `()` 类型，其行为好比 C/C++ 中的 `void` 。
-We want to return a value of `i32` type from the `square` function, but it is returning a `()` type...
+我们希望 `square` 函数返回一个 `i32` 类型的值，但现在它返回的是 `()` 类型...
-They are not the same. There are two solutions:
+它们显然是不一样的。对此有两种解决方案。
-1. Add a `return` ahead of `num * num;`
+1. 在 `num * num;` 前面加上 `return` 关键字
-2. remove `;`, make it to be `num * num`"""
+2. 移除 `;`，让它变成 `num * num`"""
 
 # IF