题目内容
4．"Keep out or I'll chase you out!This is my property!"You hear this every spring．It is a long musical sound---a bird song!Birds use their songs to communicate different messages to one another．People who study bird sounds are learning their meanings．
Usually it is the male that sings．Early in spring he sings to say that he has picked out a piece of property．He sings to attract a female of his same kind．Together they will raise a family in his territory （领地）．He sings to tell all other birds of his kind to keep out．
Each kind of bird has its own type of song．Cardinals sing something that sounds a little like"What cheer，cheer，cheer．"Towhees sing，"Drink your tea．"
Most of the time，birds pay attention only to the songs of birds of their own kind．Cardinals answer cardinals，and song sparrows answer song sparrows．A cardinal knows that a song sparrow will not try to steal its mate．So you can see one reason why a cardinal may chase away another cardinal but will not bother a song sparrow．
Most different kinds of birds eat different things．To find enough to eat，a bird needs a big piece of land to search in．Many kinds of birds have some ways of dividing up the land into territories．Song sparrows，cardinals ovenbirds，and white-throated sparrows are some of the birds that have territorial systems．
Especially in early spring，birds work out the boundaries between their territories by singing"keep out"threats and by chasing and fighting each other．The birds continue singing to tell females that they have set up territories．Neighboring birds seem to agree that there are make believe fences between their pieces of property．Then they do not have to waste energy chasing each other instead of taking care of their young．
Scientists guessed that some birds could recognize their neighbors by small differences in their songs．Two scientists who studied white-throated sparrows found that these birds can even tell the difference between songs of individual birds of their own kind．White-throated sparrows have songs that seem to say"I'm your neighbor"or"I'm a stranger"or"I'm your neighbor to the west．"Other kinds of birds could tell neighbors from strangers by their songs，too．
32．What is the article mainly about？B
A．How birds build up their territories．
B．How birds sing to communicate．
C．How male birds chase after females．
D．How scientists recognize birds'songs．
33．A cardinal may not keep a song sparrow out of its territory becauseC．
A．they sing different songs
B．they have separate territories
C．it feels no threat from a song sparrow
D．song sparrows are friendly to other birds
34．Some birds have their own territorial systems so thatA．
A．they don't need to fight or chase each other
B．they often work together against threats
C．they build up fences to protect their property
D．they find a big piece of land to search for food
35．What can we conclude from the article？C
A．Male birds use their songs to communicate more than females．
B．Scientists have learned the meanings of all white-throated sparrows sing．
C Not all birds can recognize their neighbors by small differences in their songs．
D．White-throated sparrows are the smartest birds the scientists ever found．
分析 文章主要讲述了动物界的小鸟如何通过吟唱来彼此相互交流，来传递他们的信息．
解答 32．B 主旨题．根据文章内容，主要讲述了动物界的小鸟如何通过吟唱来彼此相互交流，来传递他们的信息．结合选项，故选B
33．C 细节题．根据文章内容A cardinal knows that a song sparrow will not try to steal its mate．So you can see one reason why a cardinal may chase away another cardinal but will not bother a song sparrow．一只红雀知道一只唱歌的麻雀不会抢走它的伴侣，因此，它会给唱歌的麻雀留一个栖息之地，不会赶走它．结合选项，故选C
34．A 细节题．根据文章内容Especially in early spring，birds work out the boundaries between their territories by singing"keep out"threats and by chasing and fighting each other．由此可知，小鸟儿们也有领土意识，占据一席之地，那样它们就不用和其他鸟儿争斗和追逐．结合选项，故选A
35．C 细节题．根据文章内容Scientists guessed that some birds could recognize their neighbors by small differences in their songs．科学家猜测，一些鸟儿能够通过它们歌声中的细小差别来判断是否是它们的邻居，而并非所有的鸟儿都是这样的，结合选项，故选C
点评 本文是科教类阅读理解．做这类题材阅读理解时要求考生对文章通读一遍，做题时结合原文和题目有针对性的找出相关语句进行仔细分析，结合选项选出正确答案．推理判断题也是要在抓住关键句子的基础上合理的分析才能得出正确答案，切忌胡乱猜测，一定要做到有理有据
