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问题 解答题

一项工程，第一天甲做，第二天乙做，第三天甲做，第四天乙做，这样交替轮流做，那么恰好用整数天完工，如果第一天乙做，第二天甲做，第三天乙做，第四天甲做，这样交替轮流做，那么完工时间要+．已知乙单独完成这项工程需要20天，则甲单独完成这项工程需要______天．

答案

把这项工程总量看做单位“1”，根据题干可知，乙的工作效率是

1
20
，且甲的工作效率=乙的工作效率+甲的工作效率×
1
2
．

设甲的工作效率为x，可得方程：

x=

1
20
+
1
2
x，

1
2
x=
1
20
，

x=

1
10
，

1÷

1
10
=10（天）；

答：甲单独完成这项工程需要10天．

故答案为：10．

单项选择题 B型题

感染伤口换药为（）

A.3～5日1次

B.每日1次

C.隔1～2日1次

D.每日1～2次

E.2～3日1次
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单项选择题

Starting with his review of Skinner’s Verbal Behavior, Noam Chomsky had led the psycholinguists who argue that man has developed an innate (天生的) capacity for dealing with the linguistic universals common to all languages. Experience and learning then provide only information about the (1) instances of those universal aspects of language which are needed to communicate with other people within a particular language (2) .

This linguistic approach (3) the view that language is built upon learned associations between words. What is learned is not strings of words per se (本身), but (4) rules that enable a speaker to (5) an infinite variety of novel sentences. (6) single words are learned as concepts: they do not stand in a one-to-one (7) with the particular thing signified, but (8) all members of a general class.

This view of the innate aspect of language learning is at first not readily (9) into existing psychological frameworks and (10) a challenge that has stimulated much thought and new research directions. Chomsky argues that a precondition for language development is the existence of certain principles "intrinsic (原有的) to the mind" that provide invariant structures (11) perceiving, learning and thinking. Language (12) all of these processes; thus its study (13) our theories of knowledge in general.

Basic to this model of language is the notion that a child’s learning of language is a kind of theory (14) . It’s thought to be accomplished (15) explicit instruction, (16) of intelligence level, at an early age when he is not capable of other complex (17) or motor achievements, and with relatively little reliable data to go on. (18) , the child constructs a theory of an ideal language which has broad (19) power. Chomsky argues that all children could not develop the same basic theory (20) it not for the innate existence of properties of mental organization which limit the possible properties of languages.

3（）

A.attacks

B.assaults

C.charges

D.accuses
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