Easy
Zip your lips
Be Quiet
My brother is a couch potato
My brother is lazy and watches tv too much
Don't let the cat out of the bag!
As easy as ABC
It's easy
Piece of cake
Easy to do
They 2nd graders were as busy as bees
They were working hard
When time flies
Time passes by quickly
When pigs fly
Something that will never happen
He was in hot water
He was in trouble
Under the weather
Not feeling well
Out of the blue
With no warning
She has a green thumb
She is good at gardening and taking care of plants
Hold your Horses
Wait a minute
He was cool as a cucumber
He was calm and confident
It's raining cats and dogs
It's raining very hard
Fish out of water
Out of your comfort zone
In the same boat
Having the same problem
I'm listening to you/You have my full attention
It cost me an arm and a leg
It was expensive
He's a night owl
He stays up late