英语四级完形填空模拟题十七(附答案详解)

英语四级完形填空模拟题十七(附答案详解)

洛基英语，中国在线英语教育领导品牌

Space is 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 __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(紫外线的) penetrate the __6__ .

Cosmic(宇宙的) 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__ called“rems (雷目)”.

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

e B.live

C.eat

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