diff --git a/docs/编程入门/CS106L.en.md b/docs/编程入门/CS106L.en.md
index ac90850f..20eb6354 100644
--- a/docs/编程入门/CS106L.en.md
+++ b/docs/编程入门/CS106L.en.md
@@ -3,7 +3,7 @@
 ## Descriptions
 
 - Offered by: Stanford
-- Prerequisites: better if you are already proficient a programming language
+- Prerequisites: better if you are already proficient in a programming language
 - Programming Languages: C++
 - Difficulty: 🌟🌟🌟
 - Class Hour: 20 hours