题干

2015年9月,美国国家航空航天局宣布:在火星表面发现了有液态水活动的证据。火星上发现了有液态水活动的证据,对作出下列推断具有重要意义的是(    )

A:火星公转轨道为椭圆形

B:火星可能存在生命

C:火星自转周期比地球长

D:火星大气层稀薄

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答案(点此获取答案解析)

B

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阅读下列短文,从文后各题所给的四个选项中选出一个最佳答案。

    There was a blind girl who hated herself because she was blind. In fact, she 1 nobody except her boyfriend, for he was always 2 to help her. She used to tell her boyfriend,“If I could see the 3, I would marry you.”

    One day, someone donated (捐赠) a pair of  4 to her. When the bandages (绷带) came off, she was able to see everything, including her boyfriend, for the 5time. He asked her, "Now that you can see the world, will you  6  me?" The girl looked at her boyfriend and was greatly surprised to see that he was  7. She had never expected that. She would not like to be with a blind husband for the rest of her life, so she 8to marry him.

     Her boyfriend left in tears and a few days later wrote a 9 to her, saying, "My dear, take good care of your eyes. 10 they are yours. They were mine."

     This is how the human brain (人脑) often works when our status (地位) changes. Only a very few remember what  11 was like before. And we often ask for more than we need. Life is a gift. Today, before you complain about the 12  of your food, think of someone who has nothing to 13. Before you complain about life, think of someone who went to heaven (天堂) too early. Before you complain about your old 14, think of the people who are living in the streets. And when you are tired and complain about your job, think of those who have no jobs. So 15  what you have and don't forget your past.