Passage Two

　　Questions 62 to 66 are based in the following passage.

　　The largest shark known to us, Megalodon, is extinct. Or is it? Carcharodon Megalodon, commonly known as Megalodon, is believed to have lived between 1 million and 5 million years ago and thought to have been 52 feet long. It is (or was) a shark that had a jaw 7 or more feet wide. Fairly recently, there has been some speculation about whether it is extinct or just out of reach. But few people believe that Megalodon has found a home deep in the ocean.

　　There are many known "Living Fossils": Coelacanth, Sea Cucumbers, Sea Urchins, Lobsters, Sea Stars. The common ones like lobsters and sea urchins are not really looked on as anything amazing. They've been around for thousands of years or more, and are easily accessible to us. What if they weren't accessible and yet still existed? We would label them extinct. The discovery of a live Coelacanth, a fish long believed extinct, challenged some scientists' long-held beliefs on extinction. There have been recent discoveries of incredibly large squid, and deep-sea fish never before seen by scientists.

　　In the 1960s the U.S. Navy set up underwater microphones around the world to track Soviet submarines. The network, known as the Sound Surveillance System, still lies deep below the ocean's surface in a layer of water known as the "deep sound channel". The temperature and pressure of the channel allow sound waves to travel undisturbed. NOAA's Acoustic Monitoring Project has been using the Sound Surveillance System to listen for changes in ocean structure like ocean currents or volcanic activity. Most of the sounds recorded are common and of no concern. One sound, identified in 1977 by U.S. Navy "spy" sensors, was odd. It was obviously a marine animal but the call was more powerful than any of the calls made by any other reported sea creature. It was too big for a whale. Could it be a deep-sea monster? One possibility was a giant squid, but no one is sure. It was named "Bloop". Could it be Megalodon? If Megalodon is still alive down in the bottom of the ocean, we may some day soon discover it. Then what? Deep sea diving will never be the same, that's for sure!

　　62. The following is commonly known EXCEPT ________.

　　[A] Megalodon, the largest shark, is extinct

　　[B] Megalodon is not extinct but just out of reach

　　[C] Megalodon was 52 feet long and had a jaw 7 or more feet wide

　　[D] Megalodon lived between several million years ago.

　　63. What makes scientists doubt about the belief that Megalodon is extinct?

　　[A] The discovery of many "Living Fossils". [C] The discovery of a live Coelacanth.

　　[B] The discovery of the fossils of lobsters. [D] The discovery of the fossils of sea urchins.

　　64. What was special in their recorded sounds?

　　[A] To listen for changes in ocean structure.

　　[B] To listen for changes of ocean currents or volcanic activity.

　　[C] To Make sure whether there was a giant squid deep in the ocean.

　　[D] To follow the track of the Soviet warships under water.

　　65. What was special in their recorded sounds?

　　[A] A strange, powerful animal sound was heard. [C] A sea monster's sound was heard.

　　[B] A big whale's sound was heard. [D] A giant squid's sound was heard.

　　66. What can be concluded from the passage?

　　[A] Scientists' discoveries always change people's belief.

　　[B] There are too many secrets to be discovered.

　　[C] Megalodon may be still alive deep in the ocean.

　　[D] "Deep sound channel" allows sound waves to travel undisturbed.

　　Passage Two

　　62. B 细节题。文章第一段第三，四句指出，巨齿鲨一般被认为生活在一百万到五百万年前，它们长52英尺，下颚至少7英尺宽;该段最后一句指出，几乎没有人相信巨齿鲨没有灭绝而只是迁到了深海生活，即这一观点并不为大众所接受，故选B。本题要注意题干中的commonly一词。

　　63. C 细节题。文章第二段后半部分指出某些古老的海底生物，因为人们找不到它们所以就认为它们已经灭绝了，实际上它们仍然存在，接着列举了Coelacanth为例，故选C。

　　64. D 细节题。文章第三段第一句指出，为了追踪苏联的潜水艇，美国海军在20世纪60年代在世界范围内布下了水下扩音器，由此可知D正确。

　　65.A细节题。文章第三段第六。七句指出，从美国海军录制的声音中可以听到一个奇怪的、威力无比的动物的声音，由此可知，A正确。文章并未明确指出该声音是由什么动物发出的，故应排除B、C、D。

　　66. C 推断题。A(科学家的发现总在改变人们的观念)，B(还有很多秘密未被发现)，这两项并不能从本文中推断出来，故排除;D(“深海声道”能传播声波并使其不受干扰)，由第三段第三句可知，是声道的温度和压力能传播声波并使其不受干扰，故排除D;本文开篇第二句Or is it?提出了对巨齿鲨灭绝一说的质疑。末段倒数第四句Could it be Megalodon? 暗示Bloop有可能是巨齿鲨发出的，所以C(巨齿鲨仍然生活在深海)正确。