四川省达州市2017-2019年三年中考英语试卷分类汇编：细节推理题

细节推理题 2019 六、根据短文内容，从下面方框中选择适当的选项补全短文（本题共1小题，每小题8分，共计8分） 31．（8分） Do you have a tail？ Of course not， we know． But tails are like opinions． actually， everyone has them： fishes， birds， most reptiles， and even some of our closest relatives Since tails tirst evolved（进化） at least 500 million years ago． Geckos （壁虎）use them to store fat． birds use them to steer through the air， But for most mammals （哺乳动物）．（1）　 　Yet， as you get closer to humans on the evolutionary tree， tails disappear， Gorillas（大猩猩）don' t have them， and neither do chimps（黑猩猩） or any other apes （类人猿） including us， of course， To understand why， take a look at how we walk． （2）　 　walking like this gives us a huge advantage because unlike four﹣legged animals．which have to pour energy into every step they take， two legs take advantage of gravity（重力），which does some of the work for us． You see， each time we take a step， gravity pulls us forward．The end result is that when we walk， we use around 25% less energy than wal