diff --git a/docs/Prepositions.md b/docs/Prepositions.md
index 7a9e15e..977683f 100644
--- a/docs/Prepositions.md
+++ b/docs/Prepositions.md
@@ -298,7 +298,7 @@ His objection is quite <u>beside the point</u>.
 It's sometimes difficult to live <u>within one's income</u>.
 (要量入为出，​​有时候很困难。)
 
-介系词片语 within one's means 字面上是「在个人收入范围之内」，这是用空间介系词来比喻「不透支」。
+介系词片语 within one's income 字面上是「在个人收入范围之内」，这是用空间介系词来比喻「不透支」。
 
 ## 时间介系词
 
@@ -526,4 +526,4 @@ I <u>saw</u> that many houses <u>were destroyed</u> by fire <u>on TV</u>. （不
 <u>On TV</u> I <u>saw</u> that many houses were destroyed by fire.
 (在电视上我看到许多房子被火烧毁。)
 
-把介系词片语 on TV 移到句首，它就只能够修饰主要子句的动词 saw，意思也就变清楚了。
\ No newline at end of file
+把介系词片语 on TV 移到句首，它就只能够修饰主要子句的动词 saw，意思也就变清楚了。