Bite off more than you can chew really means...
Take on too many things
The best of both worlds really means...
You get to do/have two things you really like!
It's raining cats and dogs really means...
It's raining very heavily.
Under the weather really means...
Sick
Down to earth really means...
Chill personality
Get your act together really means...
Stop acting that way
Throw someone under the bus really means...
Tell/tattle on someone
The early bird gets the worm really means...
The first person there gets first pick/best choice
Two thumbs up really means...
It's super awesome!
A picture is worth a thousand words really means...
It is easier to show something in a picture than describe it with words
Give the cold shoulder really means...
Avoid talking to someone
Rain on someone's parade really means...
Dismiss their happiness/good news
Through thick and thin really means...
We've been through a lot of good and bad times together
Smell something fishy really means...
Something is not right and suspicious
Steal someone's thunder really means...
Take the attention away from them