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