1 at any time; no matter when 任何时候;不论何时:
You can borrow my car whenever you want.你任何时候都可以借用我的车。Don't worry. You can give it back the next time you see me, or whenever.别担心,你可以下一次见到我再还给我,或者其他什么时候都可以。
2 (used when you are showing that you are surprised or impatient) when (用于惊讶或不耐烦时)究竟什么时候:
Whenever did you find time to do all that cooking?你到底什么时候有空把饭菜做好了?