Raining cats and dogs
raining hard
Zip your lips
Be quiet
have a good time
A piece of cake
Easy
Hit the books
study
Hold your horses
wait
Break a leg
Good luck
Down in the dumps
unhappy
In hot water
Hit the sack/Hit the hay
go to bed
Ants in my pants
Can not keep still because of worry and excitement
All ears
listening attentively
Butterflies in my stomach
to be nervous or anxious
In a pickle
Being in a bad situation
Over the moon
to be extremely happy
Let the cat out of the bag
tell a secret
Costs an arm and a leg
very expensive
Cold feet
To back out of doing something because you're scared
Not my cup of tea
not something one likes
Throw in the towel
Give up
A fish out of water
Feeling uncomfortable in a situation
Joined at the hips
Always together
When pigs fly
Thinking something will never happen
In the same boat
having the same problem
Once in a blue moon
rarely happens