执行命令“INDEX on姓名TAG index name”建立索引后，下列叙述错误的是( )。
A．此命令建立的索引是当前有效索引
B．此命令所建立的索引将保存在IDX文件中
C．表中记录按索引表达式升序排序
D．此命令的索引表达式是“姓名”，索引名是“index name”
参考答案：B
解析： 执行命令建立索引以后，此命令建立的索引即为当前有效索引，系统默认按升序排列，但此命令并没有创建索引文件，因而其建立的索引不会保存在IDX文件中。
第三部分：写作（共两节，满分35分） 第一节任务型阅读（共10小题；每小题1分） 阅读下列短文，根据所读的内容在文章后的表格中填入恰当的单词。注意表格中的每个空格只填1个单词。 Global warming is one of the major environmental problems we are facing today. Scientists think a further rise in the carbon dioxide levels will make this situation worse. The greenhouse effect causes the earth’s heat to be trapped in the atmosphere, which results in the increase in temperature. This in turn has an effect on various plants and animals. Global warming makes it difficult for some of them to survive. Ozone depletion(臭氧耗损) means a drop in the quantity of the ozone in the earth’s stratosphere (平流层). The ozone hole in the Antarctic is mainly due to the release of CFCs ( a type of gas). Because of ozone depletion, humans are facing various problems such as the harmful effects of UV rays. Water pollution is caused when wastes are thrown into water. What’s more, many harmful chemicals are also put into water, which causes the deaths of many wild animals and endangers the health of humans. The increasing population is causing a loss of natural resources. This is related to various human activities. For example, overfishing has caused many kinds of fishes to die out. Forests are being cleared to meet the rising demand for paper, wood, even for land. Mining(采矿) has led to a further drop in mineral resources. If we used up all the resources, how could our children survive on this planet? These are some of the current environmental problems we are facing today. Only with an effort from each person, can we hope to save our planet from being destroyed.
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