We should protect the earth， we will have no water to drink．
| A．so | B．or | C．and | D．but |
What can we students do _____ the environment?
| A．to protect | B．protected |
| C．protecting | D．protects |
—How long have you lived in this town?
—_____ 2001.
| A．Since | B．In | C．To | D．Until |
There are five people in the room, but I know _____.
| A．both of them | B．none of them |
| C．all of them | D．neither of them |
Don’t give up _____ you will never succeed.
| A．and | B．but | C．while | D．or |
Trees can stop the sand _____ towards the rich farmland in the south.
| A．moved | B．to move |
| C．from moving | D．moves |