Have you ever wondered why birds sing? Maybe you thought that they were just happy．After all, y..

Have you ever wondered why birds sing? Maybe you thought that they were just happy．After all, y..

小题1:B小题2:D小题3:B小题4:A 试题分析：文章介绍了鸟为什么会唱歌，大部分鸟的歌声是一种警告，为了保护自己的领地不被外来者侵犯。小题1:细节题：从第二段的句子：However they sing most of the time for a very different reason．Their singing is actually a warning to other birds to stay out of their territory．可知鸟唱歌是一种警告，选B小题2:猜词题：从第二段的句子：A territory is an area that an animal, usually the male, claims (声称) as its own.可知这个单词是“领地”的意思。选D小题3:细节题：从文章最后一段的句子：This screaming is what we call a bird’s song, and it is usually enough to keep an outsider away.可知在筑巢的时候鸟的歌唱是为了赶走外来者。选B小题4:细节题：从第一段的句子：After all, you probably sing when you are happy. Some scientists believe that birds do sing some of the time just because they are happy. However, they sing most of the time for a very different reason.可知作者解释鸟的歌唱是把它和人相比较。选A