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问题 单项选择题 A1型题

射频辐射是指（）。

A.高频电磁场和紫外线

B.高频电磁场和微波

C.高频电磁场和激光

D.微波和激光

E.激光与X线

答案

参考答案：B

解析：射频辐射，是非电离辐射的一部分，主要指高频、微波。

填空题


Directions:This section consists of three groups of pairs listed in two columns, A and B. You are to match the one marked 1), 2), 3) ,4) or 5) in Column A with the one marked a, b, c, d or e in Column B. One point is given to each pair you match.
1) ______ the Grammar-Translation Method
2) ______ the Direct Method
3) ______ the Audiolingual Method
4) ______ the Cognitive Approach
5) ______ the Communicative Approach
a) The primary function of language is communication.
b) All languages originated from one language and were ruled by a common grammar.
c) Language is a system of structurally related elements for the expressions of meaning.
d) Every language has its own structures and can not be forced into the constraining pattern of Latin grammar.
e) A native speaker has in his brain a set of grammar rules which he can use to make sentences with.
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单项选择题

下列关于战时 * * 主义的说法，错误的是（）

A.苏维埃 * * 非常时期的非常措施

B.是一项可以持久实行的政策

C.使苏维埃 * * 最大限度地集中了物力和财力

D.为保卫新生的苏维埃 * * 创造了必要的物质前提
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