选填,简要介绍文档的主要内容,方便文档被更多人浏览和下载。
A. such an B. such a C. so a
D. so an
19. He has decided to give up ________.
A. to smoke B. smoking C. smoke
D. smoked
20. have you ever ________ to New York?
A. gone B. been C. going
D. went
四、完形填空 （每题 1.5分，共15分）
阅读下面短文，然后从各题所给的四个选题中选出一个最佳答案。
Cats and dogs can 21 their way home, often over long distances. We often hear 22 cats which disappear when the people 23 keep them 24 to a
new area and are later 25 back at their old home. We do not know 26
they find the way. In the same way, many kinds of birds 27 from one side
of the world to another every year. This is 28 as migration. It is thought 29 they follow the sun or the stars 30 no one can be sure.
21. A. find B. to find C. finding
D. found ( )