Places
To be between a rock and a hard place
To be in a tough spot, or in a place where not much can be done
Two birds with one stone
To take care of two things at once
To be on cloud nine
To be in a really good mood
To play by ear
To do something on how it feels, over preplanning
To go out like a light
to immediately fall asleep
To be on the chopping block/to have something on the line
likely to be fired or removed from something
The cat is in the bag (and the bag is in the rivers)
The secret is safe (and stored away)
Raining cats and dogs
To be in a really bad storm
To play dirty
To play unfairly, often to cheat
To break a leg
to wish good luck (in theatre)
To be on the clock
to be working or in a workplace for play
To go into in a nest of vipers
To have one's head in the clouds
to daydream
To play Cupid
To make people fall in love, force a relationship
A blessing in disguise
Something really bad that was actually really good in retrospect
To be cooped up
To be in a confined space/to be in one place for a long time
To be a bull in a china shop
To be really clumsy
To steal someone's thunder
to take credit or attention away from someone else
Child's play
It's really easy to do (NOT the 1988 movie)
Once in a blue moon
Very Rarely (an actual blue moon happens once every three years or so)
To be in hot water
To be in really big trouble, often with peers or superiors
To run like a chicken with his head cut off.
To run without knowing what to do
To rain check
to postpone something
To play hooky
To skip school for no good reason
To peel a pineapple
To handle a difficult situation