单选题 {{B}}第三篇{{/B}}

{{B}}Space-Age Archeology{{/B}}
It's a strange partnership, but a very effective one: Satellites and space-shuttle-carried radar are helping archeologists. How? By "seeing" through sand or through treetops to locate important archeological sites.
The traditional tools for archeologists are shovels and picks. But high technology is making the archeologist's work and time far more productive.
Take, for example, the second 1981 flight of the Space Shuttle Challenger. During the mission, a powerful, experimental radar was pointed at a lifeless stretch of desert in Egypt called the Selima Sand Sheet (part of the Sahara Desert). To everyone's surprise, the radar penetrated through the sand to the harder rock beneath. On the surface, there is a little indication that Africa's Sahara Desert was never anything but a desert. When the archeologists studied the radar images, they saw what seemed to be impossible: there was sand-buried landscape that was shaped by flowing water; traces of ancient riverbeds appeared to be over nine miles wide, far wider than most sections of the present-day Nile River. Today, the area is one of the hottest, driest desert in the world.
Archeologists dug pits along the old river banks and found clues to the past: stream-rounded pebbles (鹅卵石), Stone-Age axes, broken ostrich (鸵鸟) eggshells, and the shells of land snails. The archeologists were quite pleased with these findings. For years, they'd been finding stone axes scattered through the desert, and couldn't understand why. Now we know that early humans were living on the banks of old rivers, and left their beautiful tools behind. Some are so sharp that you could shave with them.
More recently, Landsat 4, a Special earth-mapping satellite, aided in the discovery of ancient Mayan ruins in Mexico. Lansat can, with the help of false-color imagery, "see through" much of the area. Armed with these maps, a five-person expedition took to the air in a helicopter.
By the end of the second day, the team found a stretch of walled fields that expedition members said look like '"old New England fences". They just go on, non-stop, for 40 miles. Later in the week, an ancient village was pinpointed, as was the "lost” city of Oxpemul, once found in the early 1930's but quickly reclaimed by the jungle. The findings made them able to map the extent of the Mayan civilization in about five days. Working on foot, it would have taken at least 100 years.

单选题 With the help of the space-shuttle carded radar, archeologists found ______.

【正确答案】 B

【答案解析】[解析] 该题有关具体细节，利用特征词“space-shuffle-carried radar”和“archeologists”作为答案线索词，这样在第3段的倒数第2句中找到直接答案相关句： It's a strange partnership，but a very effective one：Satellites and space-shuffle-carried radar an helping archeologists．...Take，for example，the second 1981 flight of the Space Shuttle Challenger．During the mission， a powerful，experimental radar was pointed at a lifeless stretch of desert in Egypt called the Selima Sand Sheet(part of the Sahara Desert)．To everyone's surprise，the radar penetrated through the sand to the harder rock beneath．On the surface，there is a little indication that Africa's Sahara Desert Was never anything but a desert．When the archeologists studied the radar images, they saw what seemed to be impossible：there was sand-buffed landscape that was shaved by flowing water；traces of ancient riverbeds(划线句的内容与B一致)appeared to be over nine miles wide，far wider than most sections of the present-day Nile River．

单选题 Which of the following is TRUE of the sand-buried landscape?

单选题 The stream-rounded pebbled and Stone-Age axes which were found along the ancient fiver banks show that

【正确答案】 A

【答案解析】[解析] 该题也与细节相关，利用“pebbles，Stone-Age axes”作为答案线索词，这样在第4段第句找到直接答案相关句：Archeologists dug pits along the old river banks and found clues to the past： stream-rounded pebbles(鹅卵石)，Stone-Age axes，broken ostrich(鸵鸟)eggshells，and the shells of land snails． The archeologists were quite pleased with these findings...Now we know that early humans were living on the banks of old rivers, and left their beautiful tools behind.划线结构的内容与A(在古代河岸的两旁曾经出现过人类早期的文明)一致。

单选题 "They" in the second line of the last paragraph refers to ______.

【正确答案】 B

【答案解析】[解析] 该题考察代词的指代关系。利用时态线索；they后的谓语动词是一般现在时态(一般现在时态用于表示客观事实，现在反复发生或习惯性的动作以及存在的特征、状态)，借助这个时态的意义判断they所在的句子不可能用来描述过去探险队的活动，所以C不是答案；结合前句的句意“探险队发现了一块带有围墙的地，探险队的成员说它们看起来就像古代新英格兰的围墙”判断B“一块带有围墙的地”是答案。