If something is a no-brainer...
it is an easy decision
If you take something with a pinch of salt...
you don’t completely believe something
If you hit the books...
You begin to study in a serious way
If something is up in the air...
It is uncertain or unsure
If you sit tight...
You wait patiently
If you face the music...
You accept the consequences of your mistakes or actions
If something rings a bell...
It sounds familiar
If you cut to the chase...
You leave the unnecessary details and get to the point
