[单项选择]椭圆齿轮流量计的流量指示值偏低,其原因是:①实际流量超过规定的流量范围;②发讯部件丢脉冲;③变速齿轮啮合不良;④旁路有泄漏.其中()是正确原因. A. ①② B. ①②③④ C. ①④ D. ①②④
参考答案:D
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第1题: [简答题]{{I}}Section B
Directions: In this part there are five sentences in Chinese. You should translate them into English. Be sure to write clearly.{{/I}}我想说的是,在奥运会上做志愿者(volunteer)对于年轻人是有意义的事。
参考答案:What I want to say is that to be a volunteer in Olympic games is significant to young people.
A. the second largest continent in the world B. a dangerous and unpleasant insect C. farmland in the heart of Africa D. a kind of illness that can destroy cattle 参考答案:B 答案解析:[分析] 主旨题。全文主要讲述了采采蝇的分布、外形、危害、及对非洲大陆的影响等。所以B正确。