1. Black Sheep: we use this Idiom when you have a respectable family,but there is someone who is bad ,loser or with bad reputation
Ex:
I like all my family except Adam.He is always troublemaker.He is a black sheep
2.Be a Chicken :If you want to say to someone that you are cowered,and also you want to insult him .you can say you are a chicken.
Ex:
Adam run away yesterday.He is always a chicken.
3.Let Cats out of Bags:you use this idiom when you want to ask someone to tell you all he knows or all the secrets.
Ex:
Adam,I found out everything.It is better to tell me by yourself.Let cats out of bag!
4.Fat cats:you can use this idiom when you want to describe some executives in a company .These executives are sitting in comfortable offices, take high salaries ,and get good benefits.
Ex:
We do all jobs,but they do not move from their offices.I hate these fat cats.
5.Have a Cow: When you are extremely angry,or you are anxious and worried because of something or someone.
Ex:
I had a cow when my brother got arrested.