whippersnapper
n. 傲慢的家伙,自以为了不起的年轻人,不重要的人
If you refer to a young person as a whippersnapper, you disapprove of them because you think that they are behaving more confidently than they should.
...this bunch of irresponsible young whippersnappers.
这群不负责任自以为是的年轻人
1. someone who is unimportant but cheeky and presumptuous
How can I take care of this whippersnapper?
我如何对付这个自以为是的年轻人呢?