stifle  
verb uk/ˈstaɪ.fəl/ us/ˈstaɪ.fəl/
  (NO AIR)      
  [ I or T ](使)窒息,(使)喘不上气 
to (cause to) be unable to breathe because you have no air
  He is said to have stifled his victim with a pillow. 据说他用枕头闷死了受害人。 
 We almost stifled in the heat of the city. 城里热得快让我们透不过气来了。 
   (PREVENT HAPPENING)      
 [ T ]阻止;压制,抑制;扼杀 
to prevent something from happening, being expressed, or continuing
  She stifled a cough/yawn/scream/sneeze. 她忍住没有咳嗽/打哈欠/尖叫/打喷嚏。 
 I don't know how I managed to stifle my anger. 我不知道自己是怎么抑制住了愤怒。 
 We should be encouraging new ideas, not stifling them. 我们应该鼓励创意,而不是将其扼杀。