.While building a tunnel through the mountain, ________ .
| A．an underground lake was discovered | B．there was an underground lake discovered |
| C．a lake was discovered underground | D．the workers discovered an underground lake |
The athlete fell off his bike when he _____ down the hill.
| A．cycled | B．was cycling | C．had cycled | D．is cycling |
You can’t be ______ when you camp _____ an high altitude, where the air is thin.
| A．enough careful; at | B．too careful; at | C．careful enough; on | D．too careful; on |
I’d prefer ______ in the office rather than _____ at home watching TV.
| A．working; staying | B．working; stay | C．to work; stay | D．work; to stay |
She wishes to become a beautiful girl, _____ everybody loves.
| A．the one | B．one | C．that | D．which |
Sometimes customers can’t help _____ the things they don’t really need.
| A．persuading to buy | B．to be persuaded into buying |
| C．being persuaded to buy | D．to persuade into buying |