diff --git a/sustechthesis.dtx b/sustechthesis.dtx
index 460857d..ffa62fb 100644
--- a/sustechthesis.dtx
+++ b/sustechthesis.dtx
@@ -1487,6 +1487,9 @@
 \renewcommand\mainmatter{%
   \cleardoublepage
   \@mainmattertrue
+  \ifthu@language@chinese
+    \ziju{0.12}% 调整中文字距，使得每行字数更像Word。
+  \fi
   \pagenumbering{arabic}%
 }
 \renewcommand\backmatter{%
@@ -1495,6 +1498,9 @@
   \else
     \clearpage
   \fi
+  \ifthu@language@chinese
+    \ziju{0}
+  \fi
   \@mainmatterfalse
   \thusetup{toc-depth = 0}%
 }