1. 擦屁股(capigu): clean up the mess.
Be careful! I don't want to clean up your mess again.
2. 才怪呢!太阳从西边出来了。(cai guai ne/taiyang cong xibian chulai le): when pigs fly, when hell freezes over.
He will win the championship when pigs fly.
3. 参差不齐(cenci buqi): uneven/ a mixed bag.
This class is a mixed bag,so it is challenging to teach every student.
4. 插队(cha dui): cut in front of, jump the line.
He always cuts in front of other people instead of waiting for his turn.
5. 茶余饭后(chayu fanhou): fodder for dinner conversation.
That movie star's marriage has become fodder for dinner conversation.
6. 拆东墙补西墙(chai dong qiang,buxiqiang): take from Peter to pay Paul.
Taking money from a subsidiary of our company would be like taking from Peter to pay Paul.
7. 馋(chan): greedy, "such a pig", crave for.
You are such a pig. You ate that whole box of candy.