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问题 选择题

下列说法正确的是

A．金属键是晶体中的阳离子和自由电子之间的吸引力

B．Na2O，MgO，Al2O3的熔点由低到高的顺序为Na2O < MgO < Al2O3

C．HF、H2O、NH3比同族元素形成的氢化物的熔沸点高，因为它们分子间存在叫氢键的化学键

D．CH4、CCl4、CH3Cl、NH4+、P4都是正四面体结构

答案

答案：B

B．正确。

A．不正确，金属键是晶体中自由电子及排列成晶格状的金属离子之间的静电作用。

B．正确。Na＋ Mg2＋ Al3＋离子半径越来越小，所带电荷越来越多，氧化物的晶格能越来越大，熔点由低到高的顺序为Na2O < MgO < Al2O3；

C．HF、H2O、NH3比同族元素形成的氢化物的熔沸点高，因为它们分子间存在叫氢键的分子间作用力。

D．CH4、CCl4、NH4+、P4都是正四面体结构，CH3Cl不是正四面体结构。

填空题

Part 3


Questions 19-25


·Read the following passage and answer questions 19-25.
·For questions 19-25, choose the correct answer from A, B, C and D.
·Mark your answer on the Answer Sheet.
The number of speakers of English in Shakespeare’s time is estimated to have been about five million. Today it is estimated that some 260 million people speak it as a native language. Mainly in the United States, Canada, Great Brittany, Ireland, South African, Australia and New Zealand. In addition to the varieties of English found in these areas, there are great many regional and social varieties of the language, as well as various levels of usage that are employed both in its spoken and written forms.
It is virtually possible to estimate the number of people in the world who acquired adequate work knowledge of English in addition to their own languages. The purpose for which English is learned and the situation in which such learning takes place are so varied that it is difficult to define and still more difficult to assess what constitutes an adequate working knowledge for each situation.
The main reason for the widespread demand for English is its present-day importance as a world language. Besides serving the infinite needs of its native speakers, English is a language in which some of the most important works in science, technology, and other fields are produced and not always by native speakers. It is widely used for such purpose as meteorological and airport communications, international conferences, and the spread information over the radio and television networks of many nations for the number of developing countries, especially former British colonies. Many of these countries have multi-lingual populations and need a language for internal communication as well as for international communication and for access to the scientific and technological development in the west.

According to the passage, which of the following statements is NOT true

A．Some 260 million people in the word have an adequate working knowledge of English.

B．There are some 260 million native speakers of English in the world.

C．It is also impossible to estimate the number of people with an adequate working knowledge of English.

D．People learn English for variety of reasons.
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单项选择题 A1/A2型题

下列各项不属于肝郁气滞证表现的是（）

A.胸胁胀痛

B.头痛眩晕

C.胸闷太息

D.月经不调

E.咽部异物感
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