The monument was built in honor of the explorer who was believed _____ the river.
| A．to have discovered | B．to have been discovered |
| C．to discover | D．having been discovered |
Edison was a clever boy, and ______ he was fourteen, he had learned advance mathematics by himself.
| A．whenever | B．by the time | C．the moment | D．ever since |
I ______ to go on a diet, but the dishes at the party were simply impossible to resist.
| A．had intended | B．am intending | C．intend | D．could intend |
Not until the teacher explained the importance of getting up early ______ we promise to come early.
| A．should | B．would | C．did | D．could |
—How about the party ______ at Mary’s house?
—Wonderful! Everyone had a good time．
| A．holding | B．to hold | C．being held | D．held |
This is the best way ______ I have thought of ______ the problem.
| A．that; solving | B．in which; solving |
| C．which; to solve | D．/; to solve |