No beast on Earth is tougher than the tiny tardigrade(缓步类动物).It can 26 being frozen at-272°Celsius, being exposed to the vacuum of outer space and even being 27 with 500 times the dose of X-rays that would kill a human. In other words, the creature can endure conditions that don't even exist on Earth. And researchers are looking to the microscopic animals to learn how to prepare humans and crops to handle the 28 of space travel.

The tardigrade's indestructibility stems from its 29 its environment-which may seem surprising, since it lives in 30 comfortable places, like the cool, wet patches of moss (青苔) that dot a garden wall.

But it turns out that a tardigrade's damp, mossy home can dry out many times each year. Drying is pretty 31 for most living things. It does damage to cells in some of the same ways that freezing, vacuum and radiation do. Tardigrades, however, have 32 special strategies for dealing with these kinds of damage.

As a tardigrade dries out, its cells produce several strange proteins that are unlike anything found in other animals. In water, the proteins are shapeless. But as water disappears, the proteins self-assemble into long fibers that fill the cell's 33 . The fibers support the cell's membranes (细胞膜)and proteins, preventing them from breaking or 34 .

Emulating tardigrades could one day help humans colonize outer space. Food crops could be engineered to produce tardigrade proteins, allowing these organisms to grow more efficiently on spacecraft where levels of radiation are elevated compared with on Earth.

So if humans ever succeed in reaching the stars, they may accomplish this 35 , in part, by standing on the shoulders of the tiny eight-legged endurance specialists in your backyard.

A) adaptations I) rigors

B) blasted J) seemingly

C) catastrophic K) survive

D) evolved L) tempt

E) feat M) thrill

F) interior N) unanimously

G) probing O) unfolding

H) recurrence

答案解析：

can是情态动词，后面接动词原形，此空需要一个动词原形。空格所在句句意：它能够____在 -272 摄氏度的低温下被冷冻。“survive”有“存活;幸存”的意思，“survive being frozen”表示“在被冷冻的情况下存活”，符合语境，所以选K。

being后面接动词的过去分词构成被动语态，这里需要一个过去分词。空格所在句句意：甚至能承受 500 倍于能杀死人类的 X 射线剂量。“blast”有“爆炸;冲击”之意，“be blasted with”表示“受到……的冲击”，这里指受到大量 X 射线的冲击，符合语境，所以选B。

空格在定冠词 “the” 和介词 “of” 之间，故此空需要一个名词。空格所在句句意：研究人员正关注这些微观动物，以了解如何让人类和农作物应对太空旅行的____。“rigors”有“严酷;艰难”之意，“handle the rigors of space travel”表示“应对太空旅行的艰难”，符合语境，所以选I。

its后面接名词，此空需要一个名词。空格所在句句意：缓步类动物的不毁性源于它对其环境的____。“adaptations”有“适应;适应能力”之意，“its adaptations to its environment”表示“它对环境的适应能力”，符合语境，所以选A。

空格在动词 “lives” 和形容词 “comfortable” 之间，此处需要一个副词来修饰形容词comfortable。空格所在句句意：因为它生活在____舒适的地方，比如花园墙上潮湿的青苔。“seemingly”有“看似;表面上”之意，“seemingly comfortable places”表示“看似舒适的地方”，符合语境，所以选J。

is后面接形容词作表语，此空需要一个形容词。空格所在句句意：干燥对大多数生物来说是相当____。“catastrophic”有“灾难性的”之意，“Drying is pretty catastrophic for most living things”表示“干燥对大多数生物来说是相当灾难性的”，符合语境，所以选C。

空格前为动词have，后为名词短语special strategies，空格处的词可能是及物动词的过去分词，与have搭配构成现在完成时态，共同充当句子的谓语，也可能是形容词或者副词。空格所在句句意：然而，缓步类动物有____特殊策略来应对这些伤害。“evolved”有“进化的;发展而来的”之意，符合语境，所以选D。

空格在所有格 “cell’s” 之后，需要一个名词。空格所在句句意：但随着水分消失，蛋白质自我组装成长纤维，填满细胞的____。“interior”有“内部”之意，“fill the cell's interior”表示“填满细胞内部”，符合语境，所以选F。

空格在连词 “or” 之后，与现在分词 “breaking” 并列，所以也需要一个现在分词。空格所在句句意：这些纤维支撑着细胞膜和蛋白质，防止它们破裂或____。“unfolding”有“展开;打开”之意，这里指防止细胞膜和蛋白质破裂或变形展开，符合语境，所以选O。

空格在指示代词 “this” 和副词 “in part” 之间，需要一个名词。空格所在句句意：所以如果人类成功到达星空，他们可能会部分地通过依靠你家后院里那些微小的八条腿的耐力专家来____完成这件事。“feat”有“功绩;壮举”之意，“accomplish this feat”表示“完成这项壮举”，符合语境，所以选E。