[fix] pre -> previous

README.md

@@ -29,6 +29,6 @@ ios로 custom calendar and time picker를 만들었다.
 
 ## Screen shot 📸
 
-|mainscreen|calendar select|next month|pre month|time picker|time select|
+|mainscreen|calendar select|next month|previous month|time picker|time select|
 |:---:|:---:|:---:|:---:|:---:|:---:|
 |<img src="https://user-images.githubusercontent.com/46439995/104694091-06ea0e00-574e-11eb-8ba9-f4fdc2cbae32.png" width="200" alt="main screen" />|<img src="https://user-images.githubusercontent.com/46439995/104694359-6e07c280-574e-11eb-9821-436f1c589429.png" width="200" alt="calendar selcet" />|<img src="https://user-images.githubusercontent.com/46439995/104694386-74963a00-574e-11eb-93f6-4ba278d19cdd.png" width="200" alt="next month" />|<img src="https://user-images.githubusercontent.com/46439995/104694407-7c55de80-574e-11eb-8ea7-896b8bcba28d.png" width="200" alt="pre month" />|<img src="https://user-images.githubusercontent.com/46439995/104694450-88da3700-574e-11eb-9471-6d3a096f5306.png" width="200" alt="time picker" />|<img src="https://user-images.githubusercontent.com/46439995/104829917-27d07180-58bc-11eb-9ae5-3331692f4340.png" width="200" alt="time select" />|