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问题 选择题

根据相关化学原理，下列判断正确的是

A．若X是原子晶体，Y是分子晶体，则熔点：X＜Y

B．若A2＋2D－→2A－＋D2，则氧化性：D2＞A2

C．若R2－和M＋的电子层结构相同，则原子序数：R＞M

D．若弱酸HA的酸性强于弱酸HB，则同浓度钠盐溶液的碱性：NaA＜NaB

答案

答案：D

原子晶体的熔点大于分子晶体，A 错

B 错在此反应中A2是氧化剂，D2是氧化产物，氧化性：D2<A2

C 错原子序数：R＞M

D 对，酸性越强，其对应盐的碱性越弱。

单项选择题 案例分析题

From childhood to old age, we all use language as a means of broadening our knowledge of ourselves and the world about us. When humans first 1 , they were like newborn children, unable to use this 2 tool. Yet once language developed, the possibilities for human kind’s future 3 and cultural growth increased.

Many linguists believe that evolution is 4 for our ability to produce and use language. They 5 that our highly evolved brain provides us 6 an innate language ability not found in lower 7 . Proponents of this innateness theory say that our 8 for language is inborn, but that language itself develops gradually, 9 a function of the growth of the brain during childhood. Therefore there are critical 10 times for language development.

Current 11 of innateness theory are mixed, however, evidence supporting the existence of some innate abilities is undeniable. 12 , more and more schools are discovering that foreign languages are best taught in 13 grades. Young children often can learn several languages by being 14 to them, while adults have a much harder time learning another language once the 15 of their first language have become firmly fixed.

16 some aspects of language are undeniably innate, language does not develop automatically in a vacuum. Children who have been 17 from other human beings do not possess language. This demonstrates that 18 with other human beings is necessary for proper language development. Some linguists believe that this is even more basic to human language 19 than any innate capacities. These theorists view language as imitative, learned behavior. 20 , children learn language from their parents by imitating them. Parents gradually shape their child's language skills by positively reinforcing precise imitations and negatively reinforcing imprecise ones.

请在19处填上正确答案（）

A.acquisition

B.appreciation

C.requirement

D.alternative
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单项选择题

拐卖妇女儿童罪中的儿童是指（）周岁以下的人。

A.18

B.16

C.14

D.12
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