He has butterflies in his stomach.
He's nervous.
They're going bananas!
They're behaving in a crazy way!
He's catching some z's.
He's sleeping.
They're in hot water.
They're in trouble.
I'm on cloud nine!
I'm really happy!
She's down in the dumps.
She's very sad.
on the same page
we agree
I'm all ears.
I'm listening carefully.
He's a couch potato.
He watches too much TV.
It's raining cats and dogs.
It's raining very hard.
He's all tied up.
He's very busy.
Hold your horses!
Wait! Stop!
The icing on the cake
Extra, which makes something good even better!
Put on your thinking cap.
Try to solve a problem.