Be yourself.
Be there or be square.
Be careful.
Treat others the way you want to be treated.
Neither a borrower nor a lender be.
Whatever will be will be.
Let it be.
Let me be.
Be forewarned.
to be or not to be
Be prepared.
I'll be back.
You'll be sorry.
Don't be late.
Don't be afraid.
pig out put out
art
BIG
Simple as pie
diamond in the rough
"at school taking a test"
"I am going to make it a personal mission to...."
Easier said than done.
Cut it out!Who cut the cheese?
See related links for a VERY good webpage of phrases.
Worry wart Why worry? No worries!
Ditto!