题目

阅读下面短文，掌握其大意，然后从各题所给的A、B、C或者D四个选项中选出最佳选项。 A thousand years ago, Hong Kong was covered by a thick forest. As more and more people came to   1   in Hong Kong, these trees were cut down and burnt. Now there is   2   forest left, though there are still some small areas(地方) covered with trees. We call these woods. Elephants, tigers and many   3   animals were living in the thick forest. When people came to live in Hong Kong, the   4   began to die out. Early farmers grew rice and   5   pigs and It’s good manners to be ________ while watching the raising of our national flag.A. happy B. serious C. kind D. generous