We should take ____ active part in the battle to stop the germs.
A.the B.an C. /
I’ll return the book to the library as soon as I________it .
| A．will finish | B．am going to finish |
| C．finish | D．have finished |
________ is good for your health.
| A．Taking exercise | B．Take exercise |
| C．Take exercises | D．Took exercise |
—Are there any trees on _____ sides of the new street?
—Yes, there are.
| A．other | B．another |
| C．both | D．each |
While I _____ my homework in my room, my mother _____ in the kitchen.
| A．did; cooked | B．was doing; cooked |
| C．did; was cooking | D．was doing; was cooking |
We ____ _each other since I left Shanghai.
| A．haven’t seen | B．hadn’t seen |
| C．didn’t see | D．wouldn’t see |