diff --git a/docs/并行与分布式系统/CS149.en.md b/docs/并行与分布式系统/CS149.en.md
index 21872a90..affa5a53 100644
--- a/docs/并行与分布式系统/CS149.en.md
+++ b/docs/并行与分布式系统/CS149.en.md
@@ -17,7 +17,7 @@ The goal of this course is to provide a deep understanding of the fundamental pr
 - Course Website: [CMU15418](http://15418.courses.cs.cmu.edu/spring2016/), [CS149](https://gfxcourses.stanford.edu/cs149/fall21)
 - Recordings: <http://15418.courses.cs.cmu.edu/spring2016/lectures>
 - Textbook: None
-- Assignments: <https://gfxcourses.stanford.edu/cs149/fall21>, 5 assignments
+- Assignments: <https://gfxcourses.stanford.edu/cs149/fall21>, 5 assignments.
 
 ## Personal Resources