单选题
Many people who fly at least occasionally have come down with a cold or the flu shortly after disembarking. Is the air in airborne commercial jets
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? The Association of Flight Attendants (AFA),
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which 42,000 flight attendants with 27 airlines are represented, evidently thinks so. The organization claims that the incidence of air-quality-related diseases has
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among its members and demands that prompt actions be
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to improve the conditions in the airplane cabin.
A study the AFA
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in 1997 uncovered about 1,000 self-reported incidents of headaches, dizziness and memory loss
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flight attendants and passengers. Some flight attendants were too ill to
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their safety duties, while others have been permanently disabled.
Because of airlines" efforts to
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their expenses, cabin-air filters are not cleaned
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. The complaints of flight attendants do not always give
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to correct maintenance. Airlines turned to recycled air,
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that they would reduce some of their costs. They are not required to put filters in. Airlines are
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great pressure to get their flights out
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. So they do not pay as much attention to systems that are not as
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to flight schedule and safety.
Recent research findings emphasize the concern that filters can
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engine chemicals into the cabin air. This may not happen
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every flight, but it is a persistent problem.
In a study published in October 1998 an investigation was made
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complaints of crew members
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air quality and health. More than half of the 200 subjects reported health problems they
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to cabin air. It was concluded that these health problems were consistent with
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harmful gases and substances.
【答案解析】[解析] suspend暂停；drop降低；raise增加；increase v. 增加。根据上文内容，很多乘客乘坐飞机后发现自己患了流感或感冒，由此可以推断出，与空气质量有关的疾病的发病率一直在上升，因此排除A和B；当raise做“增加”讲时，其主语是人，而该句的主语是incidence，因此可以排除raise；increase主语可以是人或者物，故选D。
【答案解析】[解析] decline减少，下降，一般指数量、价值、质量等的减少，不与expense搭配，如：The number of tourists to the resort declined by 10% last year.；cut削减，一般指价钱、产量等的削减，如：Buyers will bargain hard to cut the cost of the house they want.；shrink收缩，一般指缩水，或某物从大到小的收缩，如：The tumor had shrunk to the size of a pea.；save节省，把…存起来，一般说save money，save time，但是save不能直接与expense搭配，故选B。
【正确答案】
D
【答案解析】[解析] definitely确切地；efficiently效率高地；smoothly顺利地；regularly经常地，定期地。根据前半句“Because of airlines" effort to cut their expenses”可知，航空公司极力缩减开支，由此可以推断此处表达的是飞机座舱的空气过滤器没有定期清洗，故选D。
【答案解析】[解析] confide(向某人)吐露(隐私、秘密等)；promise承诺；ensure确保；convince使确信。从语意上来看，可排除A；从句子结构上来看，这里是过去分词短语作原因状语，B项不符合；文中句子的意思是，航空公司诉诸可循环空气，因为他们确信(通过这种方式)可以降低部分成本，ensure常用于主动语态中，convince常用搭配为convince sb./yourself of sth.，如：I"d convince myself (that) I was right. 故选D。
【正确答案】
B
【答案解析】[解析] under pressure意为“承受压力”，为固定搭配，故选B。
【正确答案】
A
【答案解析】[解析] on time按时，准时；at once立即；in line成一直线；in turn依次，轮流。根据后文的“flight schedule”可以推断出此处想表达的意思是“使航班准时发出”，故选A。
【正确答案】
C
【答案解析】[解析] influential有很大影响力的，常与介词in连用，表示在某方面有影响力；inevitable不可避免的；critical极重要的，关键的，常与介词to连用，表示对于…来说是极重要的；efficient效率高的。根据该句中的"systems”以及“flight schedule and safety”可以推断出此处要表达的是“对航班时刻表及飞行安全不起关键作用的系统”，故选C。
【正确答案】
C
【答案解析】[解析] enclose(用墙、篱笆等)把…围起来；block堵塞；introduce介绍，传入，引进；detect发现，侦查。根据前面的“filters”以及后面的“engine chemicals into the cabin air”可以推断出，此处表达的是“过滤器能将发动机中的化学物质传入座舱空气中”，故选C。
【正确答案】
B
【答案解析】[解析] 表示在某种交通工具时需要用介词on，故选B。
【正确答案】
A
【答案解析】[解析] 只有on能与investigation搭配，表示“关于…的调查”，故选A。
【正确答案】
A
【答案解析】[解析] including包括…在内，表示前面所提事物包括后面出现的事物，两者属于同一范畴，且是隶属关系，而“complaints”与“air quality and health”不属于同一范畴，故排除B；relating与attaching均须与介词“to”连用来表示“关于，与…相关联”，故排除C、D；concerning关于，涉及，后面可以直接跟名词，如：the official documents concerning the sale of this land，故选A。
【正确答案】
B
【答案解析】[解析] present提交，展现；attribute与介词to连用表示“把…归因于”；blame与介词for或on连用表示“把…归因于”；appeal sb./sth. against sth.表示“因…申诉…”。这里是一个定语从句，意思是在200名调查对象中一半以上的人都将健康问题归因于座舱空气质量不良，故选B。
【正确答案】
A
【答案解析】[解析] exposure意为“显露，暴露”，可与介词“to”搭配，如：Exposure of the body to strong sunlight can be harmful.根据句意，这些健康问题是与长期暴露于有害气体及物质当中相关，A项符合文意；exploration意为“勘探，探索”；formation意为“组成，形成”；compensation意为“补偿，赔偿”，均不符合文意。