You’re likely already familiar with Dolly—the sheep that achieved near _2_ status as the firstmammal to be cloned successfully using adult animal cells. But Dolly is not alone. The world'sfirst clone—a tadpole—was actually created as early as in 1952. And at least a dozen differentspecies have been cloned since: everything from the common cow to the _3_ guar, a type ofwild ox.

　　Animal cloning has come a long way since that first tadpole more than 50 years ago. The U.S.Food and Drug Administration's (FDA) declaration in early 2008 that food products _4_ fromthe clones of cows, pigs and goats are safe for human consumption _5_ an already growinginterest in the process.

　　Cloning may have _6_ uses besides its ability to help farmers _7_ breed quality burgers andbacon. Other potential uses _8_ the preservation of species, biomedical research, drug andorgan production and even commercial ventures.

　　It seems that finding out exactly how many cloned animals have been produced is almost asdifficult as producing them in the first place. There’s no official _9_ of clones, and laboratoriesaren't required to report every single tadpole or mouse they create. But armed with a bit ofknowledge concerning animal cloning and its _10_, it’s likely to narrow down the contestants toa possible field.

　　A) inclusive B) derived C) applications D) actually

　　E) additional F) intensified G) visualized H) celebrity

　　I) include J) typically K) compromise L) endangered

　　M) registry N) duplicates O) consistently

　　解題思路

　　1.[D]空格前后分別為句子的主語和謂語，因此空格應為副詞。前一句中的half right表明本句將要說出“真正的”答案，故選actually，說明上文提到的那些名字“事實上”是幾種克隆動物的名字。

　　2.[H]空格應為形容詞、名詞或分詞，作定語修飾status。上文提到的幾種克隆動物的名字不太為人所熟悉，而這里所講的多利羊(Dolly)很多人知曉(familiar)，故此處選用celebrity，表明多利羊“很出名”。

　　3.[L]空格在定冠詞和名詞之間，為修飾名詞的定語。From…to…結構表明空格最有可能是形容詞，這樣the...guar形式上才能與the common crow—致。該句前面提及很多不同物種被克隆了，其后舉例加以說明， 由此推斷此處應該是從“普遍”到“特殊”的列舉，endangered符合語義。

　　4.[B]空格位于that引導的從句中，從句的主語是food products,謂語是are safe,可見空格應該是修飾foodproducts的后置定語。from the clones of...表明填人空格的詞應表示某種動向且能與from搭配，最可能是過去分詞。derived符合句意，表明“源自克隆牛、克隆豬和克隆羊的食物可以安全食用”。

　　5.[F]通過分析句子成分可知，空格是主句的謂語，與an already growing interest構成動賓搭配，其主語是declaration。in early 2008提示謂語動詞為一般過去時。動詞庫中intensified“增強”能與interest;構成動賓搭配，填入空格句意通順。

　　6.[E]空格在名詞uses之前，作其定語。下一句提到克隆技術可能用于保存物種、生物醫學研究等，可知這一技術除幫農民生產出漢堡包和熏豬肉外，還有其他用途。additional符合句意。

　　7.[O]空格在動詞詞組help... breed之間，應為副詞。本段講克隆技術的好處，故填入的副詞應包含積極意義，consistently符合語境，表示“源源不斷地”生產出髙質量的漢堡包和熏豬肉。

　　8.[I]空格處應為動詞，作句子謂語。主語為other potential uses，賓語為克隆技術應用的各領域，詞庫中動詞include “包括”符合此處句意。

　　9.[M]空格位于no和介詞of之間，應為名詞，且被official修飾。本句解釋難以確切知道有多少克隆動物的原因，此處指出其中一個原因“沒有關于克隆的官方……”，registry符合句意。

　　10.[C]空格在形容詞性物主代詞its后，應為名詞。本句說的是找到更多克隆動物的方法，那就要具備這方面的相關知識，此處應選用applications，填人文中意為“只要掌握一點關于克隆及其應用的知識，就能縮小找尋被克隆的動物的范圍”。

　　It’s a good idea to apply sunscreen before heading to the beach if you don’t want to bum. Butfor marine animals like whales，they don’t have that _1_. Species like sperm whales can spendup to six hours at the ocean’s surface in between dives, _2_ in the sunlight. So how do theyprotect themselves from a serious case of sunburn?

　　It turns out that their bodies have a similar defense _3_ against the sun’s UV radiation aspeople. Blue whales—which have the lightest skin color of the three species—tan during theirsummer stay before _4_ back to their northern feeding grounds. Sperm whales don’t tan. Theycan receive an “overdose” of UV radiation during their hours at the ocean’s surface, and theyhave proteins that _5_ protect their cells from UV damage. This process is _6_ to how humanbodies produce antioxidants in response to molecules that can cause a lot of genetic andcellular damage. And fin whales escape sun damage thanks to their high levels of melanin—adark substance in the skin to protect humans from UV radiation.

　　Older whales and whales with less _7_ of melanin in their skin—like blue whales—had thegreatest level of damage in their mtDNA. Fin whales, which had the greatest amount of melanin,had the least amount of mtDNA damage.

　　Now that the ozone layer that shields Earth from UV radiation is gradually _8_, it’s importantto know what the consequences are for whales and dolphins, especially for _9_ or endangeredspecies. Although it’s difficult to tell what causes many of these skin conditions, UV damage isone cause. Even though whales have _10_ defenses to UV radiation, high exposure can stillbe harmful.

　　A) similar B) diminishing C) liability D) migrating

　　E) mutual F) mechanism G) effectively H) jerking

　　I) instantaneously J) vulnerable K) content L) baking

　　M) inherent N) perspective O) option

　　解題思路

　　1.[O]空格在指示代詞that之后，應為名詞。that所指與上一句內容有關，指“去沙灘之前先涂上防曬霜”。此處應選擇option,表示海洋動物“沒有那樣的選擇”。mechanism通常用于指事物本身內在的機制，不適宜用于指代“涂防曬霜”，故排除。

　　2.[L]空格所在句子主謂賓結構完整，且空格位于逗號后面，故應為分詞作狀語，說明鯨魚在海面逗留六小時的狀況。結合上文提到的關于“防曬”的內容，可以推斷此處應該說鯨魚每天“暴曬”六小時，故選baking最合適。

　　3.[F]雖然空格前的defense是名詞，但從句賓語部分意思仍未完整，因此空格應該還是名詞，被defense修飾作句子賓語。此處應選mechanism，表明鯨魚自身擁有防曬的“保護機制”。

　　4.[D]空格前的before是介詞，而空格后緊跟表方位的back to...，可見此處應該選用動詞的現在分詞，表明鯨魚在度過了夏天之后的“動向”。動詞庫中的migrating—詞最為恰當，填入文中表示“遷徙到北方去覓食”。

　　5.[G]空格在主語和謂語之間，故應為副詞。本句提到抹香鯨體內的蛋白質可以保護它們不受紫外線的侵害。effectively符合句意，表明這種蛋白質的保護作用很“有效'

　　6.[A]根據空格后面的內容“人體如何產生抗氧化劑以應對造成大量遺傳細胞損傷的分子”可知，本句類比了抹香鯨和人類自身的防護機制，故填人空格的詞應含“類似”的意思，similar符合句意。

　　7.[K]空格在less和介詞of之間，應為名詞。本段主要講皮膚黑色素(melanin)含量的多少決定mtDNA受損的程度。填入空格的詞應與amount近義，content“含量”符合句意。

　　8.[B]空格在be動詞和副詞gradually之后，推斷此處應為分詞或形容詞，說明現在臭氧層(ozone layer)所處的狀態。通常指負面影響的consequences提示填入空格的詞應為貶義詞，因此選用diminishing， 表明臭氧層正在逐漸變小，保護地球免受紫外線輻射的作用也在減小。

　　9.[J] or提示填入空格的詞可能是形容詞或分詞，與endangered并列;也可能是名詞，與species并列。詞庫中的名詞放入句中，句意不通。形容詞vulnerable符合句意，表示逐漸減小的臭氧層對“脆弱的”物種會產生特別嚴重的影響。

　　10.[M]空格在名詞之前，應為名詞、形容詞或分詞作定語。由上文可知，鯨魚體內有類似防曬霜的保護機制，因此 鯨魚抗紫外線輻射的能力是自身就有的，故此處用inherent最合適。