动词填空（用括号内所给动词的适当形式填空。）
1．No country ________（make）such great progress as China in the past thirty years．
2．Usually the thunder ________（hear）after the lightning．
3．You ________（not know）what the pear tastes like if you don't eat it．
4．Shortly after he knew some English，he went on ________（teach）himself French．
5．The little girl will give the flowers to the hero when he ________（appear）．
6．Sometimes clouds are so thick that they do not let much sunshine ________（come）through．
7．In the old days the working people in our country ________（look）down on．
8．The engineer ________（search） for some information on the Internet in the study while his wife was cooking in the kitchen．
9．I don't think Aunt Wu would mind ________（take） care of our children while we're away．
10．The old scientist was awarded a gold medal for what he ________（do）for the development of modern science since the mid-twentieth century．
1．has made 2．is heard 3．will not／won’t know
4．to teach 5．appears 6．come 7．were looked
8．was searching 9．taking 10．had done