Kevin is a special swimmer.He took risks to41in very cold places because he wanted people to pay attention to environmental problems.
第41题，通过结合一句中的swimmer一词，可以判断出Kevin最擅长的运动为游泳，所以第41题填swim，选B。
As a boy, Kevin visited national parks and he learned the Earth is in42condition.He felt worried, and he wanted to43the Earth. In 2009he went to swim in water near North Pole(北极)to draw people’s attention to the melting glaciers(融化的冰川).Kevin said that the swim was so painful that it would be his44time swimming in cold water. In 2016, he heard about a lake in the Himalayas(喜马拉雅山脉).It was formed by melting glaciers.He45to swim in cold water again.It was difficult to swim in the lakeThe air was so46that it was hard to breathe. He told people about his experiences on TV.He wanted people to know that glaciers in the Himalayas are disappearing47global(全球的)warming and that there’s less water for people in nearby48like China, India, and Pakistan.
第42题，通过语境可判断出此题需要填写修饰condition地球状况的形容词。下面一句he felt worried，知道主人公在感到担忧，因此，用来修饰condition地球状况的形容词只有C选项的poor最为贴切，the earth is in poor condition表示“地球正处在一个糟糕的环境下"。
第43题 ，根据上面的poor condition以及hefelt worried作为提示信息，后面一句很容易想到主人公接下来的行动是关于“改善地球环境”的行为，故填A选项的protect最合适，意思为“保护地球环境”。
第44题中be someone’s__ time doing something这个短语中，time所表达的意思为“次”，整个短语的意思则是“这是某人第几次做某事”，
第45题，结合上文语义可知，此空填D选项的decide决定最合适，decide to do表示“他决定做某事”。
第46题句子中的短语 so___that___，需要直接考虑that引导出的从句it was hard to breathe很难呼吸，意思为“空气如此稀薄”，所以此处B正确。thin的语义为“瘦瘦的”或“薄薄的”，这里所用的意思即为该词的引申义“稀薄”
第47题--此空前面的语义为“冰川正在逐渐消失”，后面的语义为“全球气候变暖”，很显然，此空前后语义之间为“因果关系”，所以此处填A选项的because of最合适，表示“因为、由于”。
第48题比较简单，只需要匹配出同位语。由于like后面的词均为不同国家，所以，like前面的总结性词为countries国家，选B选项。
From Kevin’s story, we learn two49 .We lean that people can do a lot of harm to the Earth without realizing it. Also, we learn that if we 50the waywe think,we can do something to protect our environment.With the new way ofthinking in our minds,we can enjoy a bright future.
第49题，通过Kevin的故事，我们学到了2个经验教训”。应填D选项，此处lesson的意思并不是“课程”，而是引申义“经验教训”，由此可以想到短语teach someone a lesson的意思为“给某人一个教训”。
第50题 ，句意为如果我们思考事情(或问题)的方式，结合后面一句的意思“做点事情来保护环境”。很显然，此处选C选项change语义通顺。
考题遵循“以实词为主，虚词为辅，突出词汇语境化”的原则，综合上述分析具体如下：名词辨析（48题、49题），动词辨析（41题、43题、45题、50题），形容词辨析（42题、44题、46题），介词（47题）。和去年相比，减少了动词词组和副词，其中，41题、43题、46题体现了完形填空题的解题思路：即上下文衔接和连贯理解。