题目内容
假定每一车次具有惟一的始发站和终点站。如果实体“列车时刻表”属性为车次、始发站、发车时间、终点站、到达时间，该实体的主键是 (6) ；如果实体“列车运行表”属性为车次、日期、发车时间、到达时间，该实体的主键是 (7) 。在通常情况下，上述“列车时刻表”和“列车运行表”两实体型间 (8) 联系。 （8）处填（）。
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设供应商供应零件的关系模式为SP(Sno，Pno，Qty)，其中Sno表示供应商号，Pno表示零件号，Qty表示零件数量。查询至少包含了供应商“168”所供应的全部零件的供应商号的 SQL语句如下：SELECT SnoFROMSP SPXWHERE (37) (SELECT*FROM SP SPYWHERE (38) ANDNOTEXISTS(SELECT*FROM SP SPZWHERE (39) ))； （39）处填（）。
New dictionaries are needed because English has changed more in the past two generations than at any other time in its history. It has had to adapt to extraordinary cultural and technological changes, two world wars, unparalleled changes in transportation and communication, and unprecedented (史无前例的) movements of populations. More subtly, but pervasively, it has changed under the influence of mass education and the growth of democracy. As written English is used by increasing millions and for more reasons than ever before, the language has become more utilitarian (功利的, 实利的) and more informal. Every publication in America today includes pages that would appear, to the purist of forty years ago, unbuttoned gibberish (莫名其妙的). Not that they are; they simply show that you can’’t hold the language of one generation up as a model for the next. It’’s not that you mustn’’t. You can’’t. For example, in the issue in which Life stated editorially that it would follow the Second International, there were over forty words, constructions, and meanings which are in the Third International but not in the Second. The issue of the New York Times which hailed the Second International as the authority to which it would adhere and the Third International as a scandal and a betrayal which it would reject used one hundred and fifty-three separate words, phrases, and constructions which are listed in the Third International but not in the Second and nineteen others which are condemned in the Second. Many of them are used many times, more than three hundred such uses in all. The Washington Post, in an editorial captioned "Keep Your Old Webster’’s," says, in the first sentence, "don’’t throw it away," and in the second, "hang on to it." But the old Webster’’s labels don’’t "colloquial" and doesn’’t include "hang on to," in this sense, at all. In short, all of these publications are written in the language that the Third International describes, even the very editorials which scorn it. And this is no coincidence, because the Third International isn’’t setting up any new standards at all; it is simply describing what Life, the Washing-ton Post, and the New York Times are doing. Much of the dictionary’’s material comes from these very publications, the Times, in particular, furnishing more of its illustrative quotations than any other newspaper. Why does the author say new English dictionaries are needed
外商投资企业在中国境内设立分支机构的，在汇总申报缴纳企业所得税时，可将各分支机构的盈亏相抵，按有盈利的分支机构适用的所得税率计算缴纳企业所得税。 ( )
假定每一车次具有惟一的始发站和终点站。如果实体“列车时刻表”属性为车次、始发站、发车时间、终点站、到达时间，该实体的主键是 (6) ；如果实体“列车运行表”属性为车次、日期、发车时间、到达时间，该实体的主键是 (7) 。在通常情况下，上述“列车时刻表”和“列车运行表”两实体型间 (8) 联系。 （7）处填（）。
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