diff --git a/18-microarch.Rmd b/18-microarch.Rmd
index 192361e..8299fd6 100644
--- a/18-microarch.Rmd
+++ b/18-microarch.Rmd
@@ -1,4 +1,4 @@
-# (PART) Part IV CPU的微结构 {-}
+# (PART) CPU的微结构 {-}
 
 # 运算器设计