在生产、生活中，紫外线对人的皮肤、眼睛都会造成伤害。300mm以下的短波紫外线可引起紫外线眼炎，导致

A. requires

B. responsibilities

C. reasons

D. recalls

answering the phone the receiver should pick up the phone within three rings. It is regarded to be very impolite to keep the caller waiting more than half a minute.（）

After answering the phone, Jane continues(watch) ______ TV.

Since nobody is answering the phone, they ______.

A．should have left

B．must have left

C．need have left

D．can have left

What made her father angry？

A．Linda's not answering his phone call earlier.

B．Linda's not answering the man's phone call.

C．Linda's didn't like him.

uld receive it, it was hung up.

(22)

A．I barely had enough time to finish my paper.

B．I didn't hear the phone because I was typing.

C．Someone called just as I started to work.

D．I was busy with typing and answering a phone call at the same time.

He tired to ______ answering my questions.

A．prevent

B．prohibit

C．mm

D．avoid

What did he do when he heard a knock at the door？

He______ he was answering a phone call from a client.

is regarded to be very impolite to keep the caller waiting more than half a minute.()