Bears __________ fat stores throughout the summer and fall to have energy enough to last them through their winter sleep.
| A．pack up | B．build up |
| C．bring up | D．take up |
________ the driver worn the seat belt, he _________now.
| A．Had; would have survived | B．Had; would survive |
| C．Should; would have survived | D．Should; survived |
_______life in a new city can be hard, it can broaden a person’s view of the world.
| A．Because | B．When | C．While | D．As |
I am wondering ___________ that comes first in the final exam.
| A．who is it | B．who it is |
| C．it is who | D．which it is |
Word came ________ a new railway station would be built in our city.
| A．what | B．that | C．which | D．who |
Not until Tom read his composition the second time ________ the spelling mistake.
| A．does he notice | B．he noticed |
| C．did he notice | D．he had noticed |