Under the weather
Sick
Better late than never
Better to arrive late than not to come at all
Let someone off the hook
To not hold someone responsible for something
Take it with a grain of salt
Don’t take it too seriously
It's not rocket science
It's not complicated
Hang in there
Don't give up
Wrap your head around something
Understand something complicated
It's raining cats and dogs
It's raining hard
cost an arm and a leg
very expensive
Get your act together
Work better or leave
On thin ice
On probation. If you make another mistake, there will be trouble.
Pull someone's leg
To joke with someone
Let the cat out of the bag
Give away a secret
hold your horses
wait a moment
Give someone the benefit of the doubt
Trust what someone says
Take a rain check
Postpone a plan
The ball is in your court
It's your decision
Once in a blue moon
Rarely
Pull yourself together
Calm down
Spill the beans
Give away a secret
Make a long story short
Tell something briefly
A perfect storm
the worst possible situation
break a leg
good luck
On the ball
Doing a good job
Give someone the cold shoulder
Ignore someone
Throw caution to the wind
Take a risk
We'll cross that bridge when we come to it
Let's not talk about that problem right now
Rain on someone's parade
To spoil something
Cut somebody some slack
Don't be so critical
call it a day
stop working on something
It's a piece of cake
It's easy
Add insult to injury
To make a bad situation worse
You can't judge a book by its cover
This person or thing may look bad, but it's good inside