(2020·上海浦东新区高三第二次统测)A huge lake of salty water appears to be buried deep in Mars，scientists reported this week.The presence of water raises the chances of finding life on the red planet.The discovery is based on observations by a European spacecraft.It has excited experts.Water is necessary for life，and scientists have long hoped to prove that it is present on Mars.
Cassie Stuurman is a geophysicist at the University of Texas.In 2016，she found evidence of a huge ice deposit (沉积) on Mars.“If these researchers are right，this is the first time we've found evidence of a large water body on Mars.”Stuurman said.Researchers are not yet sure how deep the area of water is.So，they cannot say whether it is an underground pool，or just an area of soft and wet soil.
In order to find the water，Italian researchers examined radar signals.The signals were collected over three years by the European Space Agency's Mars Express spacecraft.The results suggest that a 20­kilometer­wide water body lies below ice that is 1.5 kilometers thick.They believe the area is close to the planet's southern pole.
Mars is very cold，but salt in the water may have kept it from freezing.It is the same as when you put salt on a road to prevent ice from forming.The water would be extremely cold，right at the point where it's about to freeze.And it would be salty.Such conditions are not ideal for life to form.But，she said there are bacteria on the earth that have been able to survive in similar conditions.
Mars has been a popular planet for exploration，with some groups placing instruments on its surface and others examining it from space.In May，NASA launched another spacecraft，the InSight Mars lander which will dig deep into the data under the surface after it reaches a flat area of the planet in November.
语篇解读：本文是一篇说明文，介绍了科学家发现火星深处可能埋藏着一个巨大的咸水湖。
12．Where do the Italian researchers believe the water body on Mars is?
A．In a pool.
B．Above ice.
C．In soft and wet soil.
D．Near the southern pole of Mars.
解析：选D　细节理解题。根据第三段中的“They believe the area is close to the planet's southern pole.”可知，意大利科学家认为水体位于火星的南极，故D项正确。
13．What can we learn about the water on Mars from the text?
A．It is probably at the freezing point.
B．It flows on the surface of Mars.
C．It is mainly in the form of solid.
D．It is probably filled with creatures.
解析：选A　细节理解题。根据第四段中的“The water would be extremely cold，right at the point where it's about to freeze.”可知，火星上的水很冷，可能在快要结冰的状态，故A项正确。
14．What will the InSight Mars lander do when it reaches Mars?
A．Dig a hole to protect the lander itself.
B．Explore the surface of Mars.
C．Gather information under the surface of Mars.
D．Examine Mars from space.
解析：选C　细节理解题。根据最后一段中的“the InSight Mars lander which will dig deep into the data under the surface after it reaches a flat area of the planet in November.”可知，InSight火星探测器到达火星后会进行挖掘以收集火星地表以下的数据，故C项正确。
15．What is the main idea of the text?
A．Life used to exist on Mars.
B．Researchers find new species on Mars.
C．Mars will be the humans'second home.
D．Water is buried beneath Mars'surface.
解析：选D　主旨大意题。 通读全文，特别是根据第一段中的“A huge lake of salty water appears to be buried deep in Mars，scientists reported this week.”可知，本文主要介绍了科学家认为火星深处可能埋藏着一个巨大的咸水湖，故D项正确。