某地一项有关高血压的横断面研究表明:男性45~55岁组有高血压者占13%,女性占15%。从而得出结论,该年龄组男性患高血压的危险性较女性小。该结论() A. 不正确,因为没有考虑到可能存在的队列的影响 B. 不正确,因没区分发病率和患病率 C. 不正确,因为未用率作性别间比较 D. 正确 E. 不正确,因为无对照组
【简答题】III. Complete the following passage with the words in the box. Each can be used only once. A. English B. smallest C. from D. arriving E. largest Toronto is Canada’s _1_ city. It is on ...
【简答题】写出下列单词在不同句子中的词性,用中文表达。如果需要,可以查阅字典。 Word Sentence Part of speech rest While the rest of the money was used up... 1 Would you like to have a rest? 2 once Once out in the street, she walked quick...
【简答题】Tom had once worked in a city office in London, but now he was out of work.He had a large family to support, so he often found himself in difficulty.He often visited Mr.White on Sundays, told him abou...