IDIOMS 1
IDIOMS 2
IDIOMS 3
IDIOMS 4
IDIOMS 5
100

Under the weather 

Sick

100

no pain no gain

you have to work for what you want

100

spill the beans

give away a secret

100

up in the air

undecided, uncertain

100

hit the books

study

200

take a rain check 

postpone a plan

200

on the same page

understand each other and agree

200

all ears

I'm listening

200

give someone a hand 

help someone

200

let your hair down

relax and enjoy

300

piece of cake

easy

300

see eye to eye

agree

300

call it a day

consider work finished for the day

300

catch someone red-handed

find someone doing something wrong

300

when pigs fly

never

400

hit the sack 

go to sleep

400

 a no brainer 

a decision that is very obvious and easy to make 

400

keep someone in the loop

be informed and updated

400

on cloud nine

extremely happy

400

to have a lot on your plate

to have a lot to do/ be very busy

500

costs an arm and a leg 

very expensive

500

burn bridges

destroy relationships

500

have a sweet tooth

love eating sweet things

500

once in a blue moon

rarely

500

burn the midnight oil 

work late