Space is a dangerous place, not only because of meteors but also because of rays from the sun and other stars.The atmosphere again acts 1 our protective blanket on 2 .Light gets through, and this is essential 3 plants to make the food which we 4 .Heat, 5 , makes our environments tolerable and some ultraviolet rays penetrate the 6 .Cosmic rays of various kinds come 7 the air from outer space, but 8 quantities of radiation from the sun are screened off. 9 men leave the atmosphere they are 10 to this radiation; 11 their spacesuits or the walls of their spacecraft, if they are inside, 12 prevent a lot of radiation damage.Radiation is the greatest known danger to explorers in 13 .Doses of radiation are measured in 14 calledrems .We all 15 radiation here on earth from the sun, from cosmic rays and from radioactive minerals.The 16 dose of radiation that we receive each year is about two millirems; it 17 according toswheresyou live, and this is a very rough estimate.Scientists have reason to think 18 a man can 19 far more radiation 20 without being damaged; the figure of 60 rems has been agreed.
1.A.for B.with C.on D.as
2.A.stars B.sun C.earth D.space
3.A.with B.from C.under D.for
4.A.use B.live C.eat D.get
5.A.again B.also C.besides D.too
6.A.environment B.space C.atmosphere D.earth
7.A.across B.to C.from D.through
8.A.valid B.enormous C.various D.proper
9.A.As soon as B.As well as C.As much as D.As possible as
10.A.shown B.exposed C.faced D.covered
11.A.but B.because C.so D.so that
12.A.get B.make C.have D.do
13.A.earth B.atmosphere C.space D.environment
14.A.pieces B.units C.parts D.elements
15.A.receive B.accept C.bring D.catch
16.A.conventional B.commonC.general D.normal
17.A.shifts B.converts C.modifies D.varies
18.A.what B.which C.that D.why
19.A.put up with B.keep up with C.come up with D.catch up with
20.A.from B.than C.as D.away
上一篇: 英语四级考试完形填空的模拟练习题(46)
下一篇: 英语四级考试完形填空的模拟练习题(20)
意总理蒙蒂将辞职 老贝宣布将再度出山
女人更关注女人:身材衣着发型 统统打量个够!
孤独星人必备:两招教你轻松亲近陌生人
白宫种菜出书,第一夫人与养蜂人分享荣誉
DIY美食:番茄香蒜酱馅饼
福布斯2017最具权势人物榜 奥巴马登顶
体坛英语资讯:Zidane looks for excuses after derby humiliation
生活这样向前走:做很多人不会去做的21件事
体坛英语资讯:2 killed, 9 athletes, 8 others injured as nightclubs loft collapses in S.Koreas Gwangju
斯威夫特和比伯在2017年欧洲音乐大奖中获胜