________ is good for your health.
| A．Taking exercise | B．Take exercise |
| C．Take exercises | D．Took exercise |
He has a hard time the problem.
| A．works out | B．working out | C．work out | D．works out |
We are friendly ______our new classmates.
| A．about | B．in | C．to | D．with |
Could I look at your picture? --Yes, of course you ______.
| A．could | B．can | C．will | D．do |
Can you tell me ________ at that time?
| A．what were they doing | B．what they were doing |
| C．what are they doing | D．what they are doing |
I didn’t go out ___ the weather got fine.
| A．because | B．so | C．until | D．after |