正确率：6/10



Water and Life on Mars

Paragraph 1: The question of life on Mars depends heavily on the characteristics of its air and water. Mars has a relatively thin and dry atmosphere, with a high percentage of carbon dioxide compared to Earth's atmosphere. Mars tilts about 25°, which leads to seasons like those on Earth. Carbon dioxide freezes into the polar caps during the winter and evaporates into the air in the summer. This causes a fluctuation in the density of the atmosphere of up to 25 percent over the year. With so little atmosphere, the planet experiences a wide range of temperatures, heating up during the day and rapidly cooling at night. Temperatures on Mars have been measured between 225° F and 95° F.

characteristic                n.特征，特点，特色        adj.独特的，典型的

tilt v.倾斜

polar caps                      极地冰盖

evaporates v.（使）蒸发，挥发；消失，消散

fluctuation                 n.波动，起伏

P1 段落大意：火星上的生命。生命依赖于空气和水。火星大气稀薄干燥，CO2含量很高相比于地球。B ✅

冬天冻成冰盖，夏天蒸发===>这导致大气密度在一年中波动高达25%。not stable A❌

which leads to seasons like those on Earth. C ✅

气候变化很大：225° F and 95° F. D ✅

EXCEPT 故选择A

1. According to paragraph 1, all of the following are true about the planet Mars EXCEPT:

A. It has an atmosphere with a stable density year-round.

B. It has a greater amount of carbon dioxide than Earth.

C. It has a number of different seasons.

D. It experiences significant temperature variations.

Paragraph 2: Scientists remain fascinated by the possibility of liquid water on Mars. Life, as we know it, requires water so it should be a good marker of habitability. Current conditions on Mars suggest that liquid water could not occur on the surface. The low pressure and low temperature mean that ice would sublime——go straight from solid to gas——rather than melt. Water may be hiding in subsurface reservoirs, however, and stream forth for limited periods. In 2002 the Mars Odyssey orbiter detected large quantities of water ice near the surface of the southern hemisphere. Channels on the surface suggest the presence of moving water in large quantities. In 2006 Mars Global Surveyor provided pictures of gullies (channels) on the surface that could only have been produced by liquid water flowing within the past seven years. Theories exist for how climate and erosion may reveal underground ice and cause sudden floods, but specific details are still a mystery. The water probably represents flash floods that quickly evaporate and may not provide an adequate medium for the development of life. If life arose in the distant past, though, the selfish floods may have been enough to maintain organisms adapted to such environments.

habitability                n.可居住；适于居住

a good marker of habitability        适宜居住的良好标志

sublime                   adj.崇高的，壮丽的，令人赞叹的；极端的，十足的

                                    v.（化）升华；使升华；<古>使变得崇高（或高尚），使变得出众

  n.崇高的事物，壮丽的景象，绝妙的东西（the sublime）；顶点（the sublime）

subsurface                adj.地下的；表面下的        n.地表下岩石

reservoir n.水库，蓄水池；储藏，蓄积；（机器等的）贮液器，贮液槽；（病原体的）储存宿主

Mars Odyssey orbiter                 火星奥德赛轨道器

hemisphere                n.（地球的）半球；脑半球；（球体的）一半

Mars Global Surveyor                n.火星全球探勘者号

                                                       （美国国家航空航天局的火星探测卫星）

gully   n.冲沟；水沟        vt.在……上开沟        vi.形成沟

gullies                      n.冲沟（gully 的复数）

medium                    n.媒介，媒体；方法，手段；（艺术创作）材料，素材；灵媒，巫师；培养基；环境；中等，中号；存储（或打印）介质；（颜料）溶剂（如油或水）；（品质、状态）中等，中庸

                                     adj.中等的，中间的，适中的；五分熟的，半熟的；（程度、强度或数量）平均的；（颜色）不深不浅的，适中的；（投球，投球手）中速的

selfish                        adj.自私的，利己的

“自私的洪水”

P2 段落大意：科学家对火星上存在流动水的可能性十分感兴趣。不过现在的状况表明月球表面不可能出现液体流动水。固态冰直接蒸发变成气体而不是融化成液体。

2002年，奥德赛，在火星南半球探测出了大量的water ice。表面的channels证明了流动水的存在。

2006年，火星全球探勘者号提供了冲沟（channels）的照片，channels只能由于流动水流淌产生。

气候和侵蚀可能揭露地下冰并且造成了突然的洪水泛滥。详细的细节仍然是一个谜团。

2. According to paragraph 2, evidence from the 2002 Mars Odyssey orbiter supports which of the following possibilities about water on Mars?

A. The near-surface of the southern hemisphere contains more water in liquid form than in ice form.

B. The amount of moving water on the surface of Mars is probably greater than that hiding in subsurface reservoirs.

C. The occurrence of flash floods on Mars is enough to maintain certain species of organisms.

D. Water may be present under the surface of Mars and flow for short periods of time.

3. In paragraph 2, the findings of the 2006 Mars Global Surveyor suggest which of the following is likely to be true about Mars?

A. The climate of Mars has changed greatly over time.

B. Life could not have existed on Mars during the planet's early history.

C. The surface of Mars experiences erosion and sudden flooding.

D. Water on the surface of Mars is very slow to evaporate.

【2】

没有提及比较关系——>A❌

没有提及比较关系——>B❌

enough to do没有明确——>C ❌

错选B

正解D ✅

【3】正解C ✅

Paragraph 3: Astrobiologists continue to investigate whether the current situation——frozen water with occasional flash floods——was always the situation on Mars. Some surface channels on Mars could not have been produced by flash floods or geologic activity. The Opportunity rover, which landed on Mars in 2004 made two interesting discoveries in several craters on Mars. Rock layers on the sides of the craters look like the patterns inside sedimentary rocks on Earth. 【5B】Sedimentary rocks form gradually at the bottom of bodies of water as particles settle down to the bottom. Sedimentary rocks on Mars would imply that a body of water was present for hundreds of years at some point in the past. In addition, Opportunity has found countless 【5D】tiny spheres of the mineral hematite (a mineral composed of iron and oxygen) on the surface. These tiny spheres, or "blueberries" as they have come to be called, strongly resemble accretions ( accumulations) found on Earth in highly acidic stream beds. Together with rippling patterns in the stone of the surface, 【5C】the layers and blueberries make a compelling argument. Acidic, salty, flowing water must once have covered large regions of the plain where Opportunity landed. The Sun has been very slowly cooling off the past few billions of years. A warmer Sun in the past means a warmer Mars. Planetary scientists do not think the difference was enough to bring Mars up to Earth-like temperatures, but it may have been enough to support liquid water in the warmer regions of the planet.

Astrobiologists        天体生物学家

occasional                adj.偶尔的，不经常的；（家具）特定场合才使用的；（文章、演讲或宗教仪式等）在特殊场合所作的，为特殊场合所准备的；非定时的，临时的

flash floods                骤发洪水

rover n.漫游者，流浪者；探月车，（行星等）探测器，越野车；童子军（Rover/Rover Scout）；（各种运动中）自由队员；（澳橄）三人机动队员组的成员；（槌球）满门球；（打）满门球（的）球手；（射箭）远距箭靶；任意箭靶；三道粗纱机操作工人，三道粗纱机

Opportunity Rover        美国NASA的双胞胎漫游车「精神号(Spirit rover)和「机会号(Opportunity rover)，一艘已经因为失去联络而结束任务，另一艘「机会号目前仍然在火星表面继续火星探索的任务。

craters                        n.[地质]火山口；[天]环形山（crater 复数）

                                     v.形成坑；毁坏（crater 的三单形式）

crater

sedimentary adj.由沉淀物形成的，沉积而成的

particles                n.微粒；粒子；极小量；质点；小品词；碎木料（particle 的复数）

settle down   定居；安定下来；专心于

sphere                 n.（活动、兴趣、专业知识的）范围，领域；球体，球，球形；社会阶层；势力范围；<文>苍穹，天，天空；<文>天体；天体外壳；地球仪

                                vt.使……成球形；包围；放入球内

hematite                 n.[矿物] 赤铁矿

resemble                v.像，与……相似

accretion                n.积聚层，冲积层；加，积聚（过程）；积淀物，增加物；吸积

=accumulation

acidic                      adj.酸的，酸性的；产生酸的

acidic stream beds         酸性河床

rippling                  n.涟漪        adj.声如潺潺流水的；起涟漪的

v.使起涟漪；使呈波状起伏；传开，扩散（ripple 的现在分词）

rippling patterns        波纹图样

P3 段落大意：天体生物学家调查研究“冰冻的水伴随偶尔的洪水”这一现状。2004年，机遇号有两个有趣的发现：月球表面坑的一半的岩石层看起来像地球内部沉积岩石的样式。

tiny shperes/ blueberries很像地球高度酸性河床里的沉积物。

4. The word "compelling" in the passage is closest in meaning to

A. imaginative B. persuasive C. important D. clear

5. All of the following are mentioned in paragraph 3 as discoveries made by the Opportunity rover EXCEPT :

A. geologic activity in several craters

B. rocks with rippling patterns

C. Earth-like layers of rock

D. numerous pieces of the mineral hematite

6. According to paragraph 3, the discoveries made by the Opportunity Rover support which of the following findings about Mars?

A. The previously acidic, salty soil in the surface layers of Mars became increasingly dry as the Sun warmed.

B. Specific areas of Mars were once covered by moving water.

C. Temperatures on Mars were once very close to those found on Earth.

D. The channels on the surface of Mars were mostly formed from frequent geological activities.

【4】compelling=persuasive

令人信服的，有说服力的；引人入胜的，扣人心弦的；非常强烈的，不可抗拒的=有说服力的，能使人信服的

v.强迫，迫使；使发生，促使（compel 的现在分词形式）

B ✅

【5】错选B 正解 A

【6】B

Paragraph 4: Overall, Mars looks like a good candidate for past life. Water, carbon, and energy were all present in useful amounts. If life arises quickly wherever resources allow, then Mars probably had a life once. Unfortunately, we have no way to assess how common the origin of life might be. This is one of the questions scientists were asking when they explored Mars in the first place.

candidate                           n.候选人，申请者；有望体验（得到）……的人（物）；

                                                投考者，考生；攻读学位者

in the first place                  首先；起初

【7】access=evaluate        v.评价，评估，估值；求（方程式，公式，函数）的数值

P4 段落大意：火星看起来很有可能存在过去的生命。我们没有办法评估生命的起源可能有多普遍。这是科学家探索火星寻求答案的问题之一。

7. The word "assess" in the passage is closest in meaning to

A. challenge B. evaluate C. prove D. explain

Paragraph 5: Astrobiologists’ another important question to ask in the exploration of Mars has to disagree about evidence for life in the first billion years of Earth's history. Mars' history must be even more contentious. The most unambiguous evidence of life on Earth comes in the form of structural fossils, which probably did not start forming on Earth until life had been around for at least a billion years. If life did arise on Mars, it may not have been around long enough to leave that kind of evidence.

contentious adj.有争议的，引起争论的；爱争论的，好争吵的

unambiguous adj.不含糊的；清楚的；明白的

structural adj.建筑结构的；建筑用的；结构（或构造）上的

P5 段落大意：另一个重要的问题是，火星的历史很有争议，地球生命来自于结构化石的形成，它们可能是在生命出现至少10亿年之后才开始在地球上形成的。如果生命在火星上存在，还没有足够的时间使它留下证据。

If life did arise on Mars, it may not have been around long enough to leave that kind of evidence.

翻译：如果火星上确实出现了生命，那么它可能存在的时间还不够长，无法留下这样的证据。

8. In paragraph 5, why does the author discuss Earth's history?

A. To imply that the history of Mars is probably similar to that of Earth

B. To demonstrate that astrobiologists use standard procedures when exploring life on different planets

C. To demonstrate that life on both Earth and Mars probably started earlier than scientists had thought

D. To emphasize how difficult it would be to find concrete evidence of past life on Mars

错选C

正解D ✅

Paragraph 2: Scientists remain fascinated by the possibility of liquid water on Mars. Life, as we know it, requires water so it should be good marker for habitability. ■ Current conditions on Mars suggest that liquid water could not occur on the surface.■The low pressure and low temperature mean that ice would sublime——go straight from solid to gas——rather than melt. ■Water may be hiding in subsurface reservoirs, however, and stream forth for limited periods. ■In 2002 the Mars Odyssey orbiter detected large quantities of water ice near the surface of the southern hemisphere. Channels on the surface suggest the presence of moving water in large quantities. In 2006 Mars Global Surveyor provided pictures of gullies (channels) on the surface that could only have been produced by liquid water flowing within the past seven years. Theories exist for how climate and erosion may reveal underground ice and cause sudden floods, but specific details are still a mystery. The water probably represents flash floods that quickly evaporate and may not provide an adequate medium for the development of life. If life arose in the distant past, though, the selfish floods may have been enough to maintain organisms adapted to such environments.

9. Look at the four squares ■ that indicate where the following sentence could be added to the passage.

It is easy to understand why this is the case.

Where would the sentence best it? Click on a square[■] to add the sentence to the passage.

很容易理解为什么会出现这种情况。

B ✅

10. Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the 3 answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points.

A. Although water on its surface is an important indication of habitability on Mars, other features of the planet also suggest the past existence of life.

B. The discoveries of sedimentary rocks and an iron oxide mineral as well as the fact that the Sun has been cooling gradually suggest that liquid water probably existed in warmer areas of Mars in the past.

C. The duration of past life forms on Mars may have been too brief to provide fossil evidence for use in scientific study.

D. Scientific explorations have reported the presence of channels and subsurface water, which suggests the presence of liquid water on Mars and the possibility of life in the past.

E. The Opportunity rover confirmed planetary scientists' belief that frozen water beneath the surface of Mars was brought to the surface as result of sudden floods and erosion.

F. The presence of necessary elements for life such as carbon, water,and energy in useful amounts has led scientists to believe that Mars is good candidate for the develop of future life .

P1 段落大意：火星上的生命。生命依赖于空气和水。火星大气稀薄干燥，CO2含量很高相比于地球。冬天冻成冰盖，夏天蒸发===>这导致大气密度在一年中波动高达25%。which leads to seasons like those on Earth. 气候变化很大：225° F and 95° F.

P2 段落大意：科学家对火星上存在流动水的可能性十分感兴趣。不过现在的状况表明月球表面不可能出现液体流动水。固态冰直接蒸发变成气体而不是融化成液体。

2002年，奥德赛，在火星南半球探测出了大量的water ice。表面的channels证明了流动水的存在。

2006年，火星全球探勘者号提供了冲沟（channels）的照片，channels只能由于流动水流淌产生。

气候和侵蚀可能揭露地下冰并且造成了突然的洪水泛滥。详细的细节仍然是一个谜团。

P3 段落大意：天体生物学家调查研究“冰冻的水伴随偶尔的洪水”这一现状。2004年，机遇号有两个有趣的发现：月球表面坑的一半的岩石层看起来像地球内部沉积岩石的样式。

tiny shperes/ blueberries很像地球高度酸性河床里的沉积物。

P4 段落大意：火星看起来很有可能存在过去的生命。我们没有办法评估生命的起源可能有多普遍。这是科学家探索火星寻求答案的问题之一。

P5 段落大意：另一个重要的问题是，火星的历史很有争议，地球生命来自于结构化石的形成，它们可能是在生命出现至少10亿年之后才开始在地球上形成的。如果生命在火星上存在，还没有足够的时间使它留下证据。