—There was thick haze（雾霾）in our city this year．What do you think of it?
—I think ________ cars we drive，____pollution our city will have．
| A．the fewer；the fewer | B．the fewer；the less |
| C．the more；the fewer | D．the more；the less |
—Always look around________you cross the street，David．
—OK，I know，Mom．
A．until
B．before
C．unless
She looked at me________disbelief when I told her the news．
| A．with |
| B．on |
| C．in |
| D．for |
Keep________till you see the light，then turn right．
| A．walk |
| B．to walk |
| C．walked |
| D．walking |
The children decide________ their schoolyard this Friday afternoon．
| A．clean |
| B．to clean |
| C．cleaning |
| D．cleaned |
After all the students took their seats，the headmaster________．
| A．show up |
| B．show off |
| C．showed up |
| D．showed off |