At last he _____ finish the work ahead of time.
| A．could | B．was able to |
| C．could be able to | D．can be able to |
The man__________has made up his mind to win will never say "impossible".
| A．whom | B．when |
| C．which | D．who |
Only when___________ according to the directions can the medicine be quite effective.
| A．taking | B．taken |
| C．being taken | D．having been taken |
To be successful, you need to remember that ___________you might be very busy, you need to be energetic and enthusiastic.
| A．as though | B．in case |
| C．even if | D．now that |
Not until all the fish died in the lake __________ how serious the pollution was.
| A．did the villagers realize | B．the villagers realized |
| C．realized the villagers | D．do the villagers realize |
A student at a Nevada middle school opened fire on campus, wounding two l2-year-old boys and__________ a math teacher.
| A．kill | B．killing |
| C．killed | D．to kill |