My son prefers us to email each other once a week       spend half an hour on the phone every night.

Unfortunately, the aboriginal(土著) people tried in vain to win independence __________ the ruling tribe, and prejudice __________ them still continued.

We Chinese are proud ______ the great success _______ the area of science and technology .

Tired, Jim was fast asleep with his back ____ a big tree.

Johnson hasn’t felt any effect the new dieting recipe has         him since he tried to lose weight three months ago.

__about 3:00am____July 28,1976,some people saw bright lights in the sky.

_____ the rain, the football game will not be cancelled.

_____ the drought in Southwest China, millions of people had to carry water from faraway places.

His parents are convinced ____ the fact the their son always focuses his mind ___ his study.

He has little acquaintance _______ music , while he has a wide knowledge ____ painting．