A basket case	a crazy person
A bull in a china shop	someone who is very clumsy
A gray area	something unclear
A little birdie told me	someone told me a secret
A piece of cake	very easy done
A rip off	too expensive
Be in hot water	be in trouble
Be in the same boat	be in the same situation
Be second to none	be the best
Have a bee in (your) bonnet	be obsessed with an idea
Birdbrain	somone who is not very smart
Put a bug in his ear	make a suggestion
Call it a day	time to quit
Cat got your tongue?	why aren't you talking?
Cross your fingers	for good luck
Cry crocodile tears	to pretend to be upset
Curiosity killed the cat	asking may get you in trouble
Doggy bag	a bag to take home leftovers from a restaurant
Draw a blank	can't remember
Fish out of water	being somewhere you don't belong
For the birds	something that is not worth anything
Get a kick out of something/doing something	enjoy something very much
Get cold feet	be nervous
Get off your high horse	quit thinking you are better than others
Get your act together	behave properly
Give it a shot	try
Give someone the cold shoulder	Ignore someone
Goose is cooked	now you're in trouble
Have a change of heart	change your mind
Have a shot at	have a chance
Have mixed feelings	unsure how you feel
Have second thoughts	have doubts
Hold your horses	wait a minute
Horse of a different color	something that is different
Hot dog	a person doing athletic stunts that are dangerous
I am all ears	You have my undivided attention
It costs an arm and a leg	it was expensive
It is in the bag	it is a certainty
A different kettle of fish	something is completely different
Let the cat out of the bag	tell a secret
Make a mountain out of a molehill	Make something that is not important into a big deal
Out of the blue	with no warning
Pig out	to eat a lot
Play it by ear	improvise
Raining cats and dogs	it is raning very hard
Read between the lines	find the hidden meaning
See eye to eye	agree
It slipped my mind	I forgot
Speak your mind	say what you really feel
The icing on the cake	something additional that turns good into great
Wolf in sheep's clothing	a person who pretends to be nice but is not
You can't teach an old dog new tricks	It is harder to older people to learn new things