The Chinese fairy story Flying to the Moon now turns to be true, with China【C1】______the country’s second unmanned lunar probe,

admin2013-04-08  24

问题     The Chinese fairy story Flying to the Moon now turns to be true, with China【C1】______the country’s second unmanned lunar probe, Chang’e 2 on 1st October, 2010. This mission marked another step for China’s pursuit of moon exploration. In fact, people all over the world have been and are【C2】______developing technologies for the exploration of deep space and the peaceful use of outer space, as space is actually a dangerous place, not only because of meteors (流 星) but also because of rays from the sun and other stars. The atmosphere again acts【C3】______our protective blanket on【C4】______. Light gets through, and this is essential【C5】______plants to make the food which we【C6】______. Heat,【C7】______, makes our environments tolerable and some ultraviolet rays (紫外线的) penetrate the【C8】______. Cosmic (宇宙的) rays of various kinds come【C9】______the air from outer space, but【C10】______quantities of radiation from the sun are screened off.【C11】______men leave the atmosphere they are【C12】______to this radiation; 【C13】______their spacesuits or the walls of their spacecraft, if they are inside, 【C14】______prevent a lot of radiation damage. Radiation is the greatest known danger to explorers in【C15】______. Doses of radiation are measured in【C16】______called "rents (雷目)". We all【C17】______radiation here on earth from the sun, from cosmic rays and from radioactive minerals. The "【C18】______" dose of radiation that we receive each year is about two millirems; it【C19】______according to where you live, and this is a very rough estimate. Scientists have reason to think that a man can【C20】______far more radiation than without being damaged; the figure of 60 rems has been agreed.
【C3】

选项 A、for
B、with
C、on
D、as

答案D

解析 固定搭配。本句意为大气层起到保护伞的作用。act as意为“充当,起……作用”,act for意为“代表,代理”,act on意为“对……起作用,按照……而行动”。根据语意,这三个选项都不对。
转载请注明原文地址:https://jikaoti.com/ti/jDVFFFFM
0

最新回复(0)