___________, you will get good grades.( )
A.If you will work hard
B.If you work hard
C.If you worked hard
The mobile phone has changed people’s life a lot ________ it was invented.
Getting enough sleep is good for _______ health _______ study.
— Hey, boy. You can’t cross the street now. You have to wait _______ the traffic lights turn green. — Oh, sorry and thank you.
Mom was cooking ________ Dad was reading newspapers.
It’s late. David washes his face _______ goes to bed.