Part Ⅳ Cloze Test (10 points)

Directions: There are 10 blanks in the following passage. For each numbered blank, there are 4 choices marked A, B, C and D. Choose the best one and mark your answer on the ANSWER SHEET with a single line through the centre.

Perhaps more than anything else, scientists are eager to find out if Martian life existed in the past-or still exists. ___76___ telescopes first zoomed in ___77___ Mars in the 17th century, people have conjured up a wild ___78___ of images or what Martians might look like. But space probes like the 1997 Sojourner land rover have yielded no evidence of such alien beings.

Most experts agree that if life did at one time evolve on Mars, finding evidence of that life-which would likely take the form of tiny organisms-won't be easy. ___79___, many scientists are optimistic. "We've got organisms on Earth that adapted to life deep ___80___ the surface in underground water wells,"says Stephen Clifford. "___81___ life like that evolved on Mars four billion years ago, there's no reason why it ___82___ today."

___83___ last year's disappointing losses, the future of Martian exploration looks ___84___. This year, two major films about fictitious Mars missions-Red Planet and Missions to Mars-are certain to heighten interest in our planetary neighbour. More important, plans for new sets of NASA orbiters and landers-one to launch in 2001, the other in 2003-are already in the works. Without a doubt, each new mission will inch scientists closer to ___85___ the mysteries of planet Mars.

1. A. When B. Before C. Ever since D. Ever

［答案］C

【精析】本文第一句點(diǎn)明了全文中心思想：科學(xué)家們正渴望發(fā)現(xiàn)火星生命是否過去存在過或現(xiàn)在仍然存在。第二句為主從復(fù)合句，主句的時(shí)態(tài)為現(xiàn)在完成時(shí)，那么引導(dǎo)時(shí)間狀語(yǔ)從句的連詞必然是since，為加強(qiáng)語(yǔ)氣可用選項(xiàng)C中的Ever since.

2. A. in B. on C. in the D. on the

［答案］B

【精析】本題的難點(diǎn)在于辨別出短語(yǔ)動(dòng)詞zoomed in的意思是“（鏡頭）拉近，推近”，如：The TV camera zoomed in on the child's face. 電視攝像機(jī)向孩子的臉部推近。on Mars 是固定搭配，Mars前面不加the，且下文有反復(fù)出現(xiàn)。

3. A. varying B. various C. plenty D. variety

［答案］D

【精析】本句的大意是：人們想象出火星的各種各樣的雜亂形象...a variety of 是固定搭配，plenty of 也含有 “許多”的意思，但前面沒有不定冠詞a.

4. A. Still B. Even if C. Though D. Although

［答案］A

【精析】前句談到了大部分專家認(rèn)為火星上曾經(jīng)有生命，但找到有生命的證據(jù)不是容易的。本句接著講許多科學(xué)家仍很樂觀，可以從句意和語(yǔ)法兩方面推理，副詞still為正確答案。

5. A. up B. under C. below D. above

［答案］C

【精析】本句的大意是：我們?cè)诘叵滤姓业竭m合生活在很深的地表下面的微生物。按邏輯推理可選擇under 或below，但under指在某物的正下方，含垂直在下的意思，而below指在某物下面，但不一定在正下方，范圍較寬，所以選項(xiàng)C為正確答案。

6. A. When B. What C. That D. If

［答案］D

【精析】本句的大意是：如果在億萬年前火星上存在有這樣的生命，就沒有理由說今天不會(huì)存在這樣的生命。從意義和句法結(jié)構(gòu)來判斷，選項(xiàng)D的if為正確答案。

7. A. wouldn't exist B. wouldn't have existed

C. doesn't exist D. has existed

［答案］A

【精析】通過上題可知道本句是表示與現(xiàn)在事實(shí)相反的非真實(shí)條件句，主句的謂語(yǔ)動(dòng)詞形式為：would + 動(dòng)詞原形，因此選項(xiàng)A為正確答案。

8. A. Even if B. Despite C. Although D. However

［答案］B

【精析】本句的大意是：盡管去年有令人失望的損失，但火星探測(cè)的前景看來是有希望的。Even if與Although需連接從句，Despite后可跟名詞或短語(yǔ)。通過意義和邏輯推理，可選擇Despite（盡管）為正確答案。

9. A. promised B. being promised

C. promising D. to be promised

［答案］C

【精析】本句中謂語(yǔ)動(dòng)詞looks為連系動(dòng)詞，后面應(yīng)跟形容詞做表語(yǔ)，只有promising（有希望的）既滿足意義的要求，又符合謂語(yǔ)動(dòng)詞的構(gòu)成。

10. A. understand B. understanding

C. be understood D. the understanding

［答案］B

【精析】本句的大意是：毫無疑問，每一項(xiàng)新的任務(wù)都會(huì)使科學(xué)家逐步接近了解火星的秘密。句中的to為介詞，后面應(yīng)接動(dòng)名詞understanding.