After a long walk, they______ pass over the mountain.
| A． could be able to | B．can | C．would | D．were able to |
--Who did you ___ in the street last Sunday?---Lin Tao, a good friend of mine.
| A．run away | B．run for | C．run into | D．run after |
Something ___ to save our earth. Do you think so?
| A．can do | B．must do | C．has to do | D．must be done |
I’ m sorry, I mistook you ___ your sister ___ mistake.
| A．for, by | B．by, for | C．by, by | D．for, for |
The scientists are trying to ___ natural energy to decrease air pollution.
| A．make friends with | B．make full use of | C．make notes of | D．make into |
China is ___ the east of Asia while Japan is ___ the east of China.
| A．in, on | B．on, to | C．in, to | D．to, on |