Shortly after we ______, a waiter came over to us with a smile.
| A．sat | B．seated | C．was seated | D．seated ourselves |
The audience waited until the curtain rose and then_____ laughter at the sight of the funny actor.
| A．burst out | B．burst into | C．broken into | D．began with |
The manager o
f the company told us that very little_____ was made of the waste material in the past.
| A．cost | B．value | C．use | D．matter |
An advertisement is useful in_____ it can persuade customers to buy the kinds of goods in the shop.
| A．that | B．which | C．what | D．whether |
—Why didn’t you apologize to her?
—She drove away ______ I could say a word.
| A．before | B．after | C．until | D．unless |
____ private cars are bringing us convenience, they may also cause more traffic accidents and pollution.
| A．While | B．As | C．If | D．Since |