diff --git a/1000-hours/sounds-of-american-english/2.5.1-pitch.md b/1000-hours/sounds-of-american-english/2.5.1-pitch.md
index c60f5ba8..d0df33bb 100644
--- a/1000-hours/sounds-of-american-english/2.5.1-pitch.md
+++ b/1000-hours/sounds-of-american-english/2.5.1-pitch.md
@@ -28,8 +28,8 @@ Pitch control mainly relies on the *larynx*. *tone* ([2.5.2](2.5.2-tone)), which
 
 <video controls width="720"> <source src="/videos/CatherineAnderson.mp4" type="video/mp4"></source>Your browser does not support the video tag. </video>
 
-之所以 “说话” 只不过是 “极其低配版的歌唱”，是因为它的曲调（*Melody*）只是在一个特别狭小音高区域（*Pitch region*）里变化。
+之所以 “说话” 只不过是 “极其低配版的歌唱”，是因为它的曲调（*Melody*）只是在一个特别狭小音高区域（*Pitch range*）里变化。
 
-The reason why *speaking* can be considered as *extremely pared-down singing* is because its melody (prosody) only fluctuates within a very narrow pitch region.
+The reason why *speaking* can be considered as *extremely pared-down singing* is because its melody (prosody) only fluctuates within a very narrow pitch range.
 
-[^1]: The video clip came from *[Essentials of Linguistics, 2nd edition](https://ecampusontario.pressbooks.pub/essentialsoflinguistics2/)*，and the narrator is one of the authors, Catherine Anderson。
\ No newline at end of file
+[^1]: The video clip came from *[Essentials of Linguistics, 2nd edition](https://ecampusontario.pressbooks.pub/essentialsoflinguistics2/)*，and the narrator is one of the authors, Catherine Anderson。