diff --git a/docs/电子基础/signal.en.md b/docs/电子基础/signal.en.md
index ca18dff0..e570d099 100644
--- a/docs/电子基础/signal.en.md
+++ b/docs/电子基础/signal.en.md
@@ -12,10 +12,10 @@ The essence of this course is the 6 incredibly interesting Labs that will allow
 
 ## Course Resources
 
-- Course Website: https://inst.eecs.berkeley.edu/~ee126/fa20/content.html
+- Course Website: <https://inst.eecs.berkeley.edu/~ee126/fa20/content.html>
 - Recordings: refer to course website
 - Assignments: refer to course website
 
 ## Personal Resources
 
-All the resources and assignments used by @PKUFlyingPig in this course are maintained in [PKUFlyingPig/UCB-EE120 - GitHub](https://github.com/PKUFlyingPig/UCB-EE120)
\ No newline at end of file
+All the resources and assignments used by @PKUFlyingPig in this course are maintained in [PKUFlyingPig/UCB-EE120 - GitHub](https://github.com/PKUFlyingPig/UCB-EE120)