— Is it convenient for you to have a drink together this evening?
— Sorry. That’s _______ I will be meeting an important guest at the airport.
| A．because | B．when | C．why | D．what |
The discovery of these tombs is _______ for scholars’ studying the history of the Tang Dynasty.
| A．of very important | B．great importance |
| C．of great significance | D．great significant |
Life ____ be much happier if we ____ only be born at the age of 80 and gradually approach 18.
| A．will, can | B．will, could | C．would, can | D．would, could |
After floods had destroyed crops and houses, the farmers in the village were _____ food and shelter.
| A．for lack of | B．for short of | C．in want of | D．in the need of |
Never lose _____ heart. There is always a chance of _____ weak defeating _____ strong.
| A．×; the; the | B．the; the; the | C．×; ×; × | D．a ; the; the |
Everyone can borrow from this public library only two books _____ and they must be returned within a month.
| A．at one time | B．at times | C．at the time | D．at a time |