pig-headed
adjective /ˌpɪɡ ˈhedɪd/
  /ˌpɪɡ ˈhedɪd/
 - unwilling to change your opinion about something, in a way that other people think is annoying and unreasonable顽固的;固执的 - Why are you being so pig-headed about this?你为什么对这件事如此固执? 
 
- Why are you being so pig-headed about this?