Merge pull request #571 from songhahaha66/patch-1

Fix mutable borrow error in borrowing.md example

Author: sunface

solutions/ownership/borrowing.md

@@ -147,8 +147,8 @@ fn main() {
     let r1 = &mut s;
     let r2 = &mut s;
 
-    // add one line below to make a compiler error: cannot borrow `s` as mutable more than once at a time
+    // Add one line below to make a compiler error: cannot borrow `s` as mutable more than once at a time
     // you can't use r1 and r2 at the same time
-    println!("{}, {}", r1, r2);
+    println!("{}", r1);
 }
 ```