Rain/animal idioms

Sentence: It has been raining cats and dogs since last night. Many were evacuated from their houses, in case there is a flood.

Sentence: I am feeling a bit under the weather these days. I think I'm getting a cold.

Sentence: I told everyone to keep the party a secret, but my mum found it out. Someone must have left the cat out of the bag. But who?!

Sentence: - Free food everybody!

-Did you hear that? I am going to pig out as much as I can.

• We pigged out on ice cream until we started to feel sick.