1、what are you doing？意思是你在干什么？

2、例句：（1）what are you doing，mon？I need your help.你在干什么妈妈？我需要你的帮助。（2）what are you doing？How can you see?你在干什么？你怎么能看得见？

3、what are you doing？是特殊疑问句，what are you后要加动词的ing形式。例如：（1）What are you drinking?你在喝什么呢？（2）What are you waiting for？你在等什么？