diff --git a/content/en/docs/b5.impls-and-traits.md b/content/en/docs/b5.impls-and-traits.md
index c1baa36..71ba9a4 100755
--- a/content/en/docs/b5.impls-and-traits.md
+++ b/content/en/docs/b5.impls-and-traits.md
@@ -119,7 +119,7 @@ fn main() {
 
 ```rust
 trait From<T> {
-    fn from(T) -> Self;
+    fn from(t: T) -> Self;
 }
 
 impl From<u8> for u16 {