—What do you use the box_____?
—I use it_____keep pencils,rulers,pens and so on.
A.to, to B.to, for C.for, to
It is said that the gravity on Mars is only about __________ of the gravity on earth．
| A．three-eighths | B．third-eighth |
| C．three-eighth | D．third-eighth |
While Helen _____ along the river after supper, she ____ a wallet lying on the roadside.
A. was walking; was finding B. walked; found
B. walked; was finding D. was walking; found
I stopped the car ____ a short break as I was feeling tired.
| A．take | B．taking | C．taken | D．to take |
______ the students were when they heard the rock music!
| A．How excited | B．How exciting |
| C．What excited | D．What exciting |
______ you keep trying till the end, you will never know how strong you are!
| A．Although | B．If |
| C．Unless | D．Because |