第3题: [单项选择]面部疖肿手术时，皮肤消毒比较正确的方法 A. 先用3%碘酊，后用70%酒精，由手术中心向周围涂擦皮肤 B. 先用3%碘酊，后用70%酒精，由手术周围向中心涂擦皮肤 C. 70%酒精，周围向中心涂擦皮肤 D. 70%酒精，中心向周围涂擦皮肤 E. 1:1000新洁尔灭，中心向周围涂擦皮肤 参考答案:C
第7题: [单项选择]In writing the passage, the author intends to______. A. give an accurate description of the possible disaster in the future B. prove that humans will sooner or later be destroyed C. tell the historical development of the Earth D. warn of a possible disaster in the future 参考答案:D 答案解析:[解析] 在这篇短文中，作者讲述了2094年彗星撞击地球后可能产生的灾难，目的是为了警告人们在未来地球可能会遭受灾难。所以正确的答案为D。
第8题: [单项选择]What do we know about modern bows A. They are accurate and easy to pull. B. Their shooting range is 40 yards. C. They are usually used indoors. D. They took 100 years to develop. 参考答案:A
