Animal
Food
Weather
100

When someone is not saying anything.

Cat got your tongue?

100

When someone is very lazy

Couch potato

100

To be unaware of what is going on because you are daydreaming

Head in the clouds

200

When something is surprising.

Holy cow!

200

When someone is cherished above all others

The apple of my eye

200

To be scared to do something

Cold feet

300

When it's raining very hard.

Raining cats and dogs

300

Someone who is bad 

Bad egg

400

to solve to problems with one solution

Kill two birds with one stone

400

When something is very easy

Like taking candy from a baby

500

To admit you were wrong about something

Eat crow

500

To drive a car that does not work well

Drive a lemon