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阅读模拟题：
Scientists have been puzzled by the phenomenon that migrating birds fly not just in groups all the time,but in"V"formations and they have tried to figure out what benefit birds get from this particular formation.Now,a research group from University of London may have found the answer―migrating birds fly in a"V"to save energy,according to a study published in the journal Nature.
When a bird flaps(振翅)its wings,it stirs the air around it and causes it to move indifferent directions.Scientist found in the study that the air creates an upward-moving wave at the tips of the wings,which means that if a bird flies around the wingtips of another bird,it can get a boost(抬高)from the rising air and therefore use less energy to stay in the air.
Apart form the"free ride"strategy,scientists were also surprised to observe that migrating birds timed their wing beats and adjusted their positions in a very precise way to maximize the lifting effect while avoiding areas where the air move downward.
"They're able to sense what's going on from the bird in front,where this'good air'is coming from and now how to position themselves perfectly in it,"lead researcher Steven Portugal told BBC.
In fact,the"V"formation has long thought to help birds fly more efficiently(效率搞地).A previous study showed that birds'heart rates went down when they were flying together in a"V"formation.Jet fighters were also found to be able reduce their energy use by up to 18%by staying near the wingtips of other jet fighters.Both of these findings led scientists to suspect that the"V"formation had an efficiency purpose,but until now they still lack proof.
"For scientists,the new study provides an insight into an interesting natural phenomenon.But it could mean even more for aircraft companies—helping them understand how they can imitatethat with their plane formations to save fuel,said Portugal."
1、According to the recent study,when birds migrate.A.they don't change their lead birds during the whole journey
B.they fly in"V"formations to protect themselves against enemies
C.they form the shape of a"V"to make best use of the lifting effect
D.the air they stir around makes it hard for the birds behind to fly fast
参考答案：C
参考解析：推理题。根据文章第三段Apart form the"free ride"strategy,scientists were also surprised to observe that migrating birds timed their wing beats and adjusted their positions in a very precise way to maximize the lifting effect while avoiding areas where the air move downward.可知候鸟按照V字形飞行是为了更好地利用鸟儿拍打翅膀带来的lifting的影响，让飞行的效率更高。故C正确。
2、What is the author's purpose in writing this article?A.To explain how birds benefit from migration.
B.To introduce how migrating birds find their way.
C.To tell some applications of migrating birds'"V"formations.
D.To report new findings about migrating birds'"V"formations.
参考答案：D
参考解析：推理题。根据文章主题段第一段最后一句Now,a research group from University of London may have found the answer―migrating birds fly in a"V"to save energy,according to a study published in the journal Nature.可知本文是对候鸟使用V字形飞行的原因的研究的新的发现。故D正确。
3、The underlined word"imitate"in the last paragraph most probably means"".
A.use
B.copy
C.change
D.learn
参考答案：B
参考解析：猜测词义题。根据本句But it could mean even more for aircraft companies—helping them understand how they can imitate that with their plane formations to save fuel,said Portugal."可知这一新发现能够帮助那些飞机制造商，更好地理解他们如何模仿鸟儿的这一飞行特点来改造飞机以节省燃料。该该词是指“模仿”，故B正确。
4、What is the significance of the new study according to this article?A.It might inspire aircraft companies to think of ways to improve efficiency.
B.It has proved that the"V"formation can improve in efficiency in many fields,
C.It has led scientists to discover that birds'heart rates go down when they fly in a"V".
D.It shows that the best formation of jet fighters in battle should be a"V"formation.
参考答案：A
参考解析：推理题。根据文章最后2行.But it could mean even more for aircraft companies—helping them understand how they can imitate that with their plane formations to save fuel,said Portugal."可知飞机制造商可以利用这一研究结果来提高飞机飞行的效率。故A正确。
