21. Bubbles， flaws， and other irregularities diffuse the light that passes through stained glass， _________ the glass sparkle.

A. which making

B. and making

C. making

D. to making

答案：C

分析：空格前的句子結(jié)構(gòu)完整，這里的分詞作狀語。A中用which來引導(dǎo)非限制性定語從句，而句中無謂語，錯；B中and作為連接詞，而and后的句子不完整，沒有謂語，錯；D錯，不定式的結(jié)構(gòu)應(yīng)該是to do.

參考譯文：氣泡，裂紋和其他的不規(guī)則會使光線穿過受損的玻璃時發(fā)散開，使得玻璃閃閃發(fā)光。

補(bǔ)充： stained glass常指教堂的彩色玻璃

22. Fog is common near _________ inland bodies of water and along coasts in temperate zones.

A. there are large

B. large

C. either large

D. where large

答案：B

分析：A使得句中出現(xiàn)兩個謂語動詞，且中間無連接詞，錯；C應(yīng)該是either… or…結(jié)構(gòu)，但句中沒有出現(xiàn)or；D中where引導(dǎo)的句子不完整，錯。

參考譯文：霧通常在靠近大型內(nèi)陸水體和沿著溫和地帶邊緣的地方發(fā)生。

23. The portrayal of everyday life in the objects of folk art makes it _________ valuable source of history.

A. and a

B. so that a

C. a

D. is a

答案：C

分析：make結(jié)構(gòu)，make+n.1/pron+n.2/adj.

參考譯文：描述日常生活的民間藝術(shù)品使它們本身成為有價值的歷史來源。

24. _______ by the United States government's Bureau of Labor Statistics， the Consumer Price Index compares current costs of goods and services with past costs.

A. To prepare

B. As it prepared

C. When preparation

D. Prepared

答案：D

分析：由后半句可以知道句子的邏輯主語應(yīng)該是Consumer Price Index， 而且空格后是by，所以應(yīng)該用被動形式，只能選D.

參考譯文：消費(fèi)者價格索引是美國政府勞工統(tǒng)計部完成的，它把現(xiàn)在的物品價格跟以前的做了比較。

25. _________ carries the genes， which determine the hereditary characteristics of the cell or organism.

A. The chromosome

B. The chromosome that

C. Whereas the chromosome

D. There is a chromosome

答案：A

分析：該句是非限制性定語從句，前半句已經(jīng)有謂語和賓語，缺主語，選A.

參考譯文：染色體攜帶了遺傳物質(zhì)，這些遺傳物質(zhì)決定了細(xì)胞和生物體的遺傳特性。

26. _________ directly with most metals to form compounds called carbides.

A. Carbon reacting

B. Carbon reacts

C. The reaction of carbon

D. When carbon reacts

答案：B

分析：從句意來看，called在這里不是謂語動詞，而是分詞做后置定語：…… which are called carbides.空格中缺主語和謂語，選B.

參考譯文：碳直接跟大部分金屬反應(yīng)而形成碳化物的化合物。

27. Meteorites are slowed down by Earth's atmosphere， but if they are moving _________， they can form a crater on impact.

A. enough fast

B. fast enough

C. so fast enough

D enough are fast

答案：B

分析：enough的用法，固定順序：adj.+enough

參考譯文：隕石受地球大氣阻擋而慢下來，但如果他們移動的足夠快，他們能在撞擊后形成一個大坑。

28. Located at the upper end of each________ an adrenal gland， an integral part of the endocrine system.

A. kidney which is

B. kidney is

C. kidney being

D. kidney

答案：B

分析：該句為簡單句，而且使用了倒裝形式，原句為：An adrenal gland， an integral part of the endocrine system is located at the upper end of each kidney.

參考譯文：腎上腺是內(nèi)分泌系統(tǒng)的一個完整的部分，它位于腎的上端。

29. About 75 percent of all cadmium is used for cadmium plating of _________ such as iron and steel.

A. easily corroded metals

B. metals are easily corroded

C. corroded metals that easily

D. how easily metals corroded

答案：A

分析：B中的are多余，否則句中出現(xiàn)兩個謂語，錯；C中的that引導(dǎo)定語從句，而從句缺謂語，錯；用法錯誤，of后一般接名詞。

參考譯文：75％的所有鎘金屬都用來對類似鐵、鋼的容易腐蝕的金屬進(jìn)行鎘鍍膜了。

30. An atom is a basic structural unit of matter， the smallest particle of an element _________ into chemical combination.

A. that can enter

B. can it enter

C. when entering it can

D. that enters can

答案：A

分析：that引導(dǎo)定語從句，element為先行詞。the smallest particle of an element 是 a basic structural unit of matter的賓語同位語。

參考譯文：原子是物體的基本結(jié)構(gòu)單元，是元素形成化學(xué)組合特性的最小的顆粒。