Read the following passage. Orcas are large predatory whales whose typic

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问题     Read the following passage.
    Orcas are large predatory whales whose typical coloration is mostly black with some white patches. In recent years, however, sightings of an unusual, almost completely white orca have been reported in the northern Pacific Ocean. One sighting of a white orca occurred near Alaska in 2000. Another sighting of a white orca—nicknamed "Iceberg" by scientists—was made off the coast of Russia in 2010.
    Because a white orca is so unusual, some scientists have suggested that "Iceberg" , the whale seen off the coast of Russia, was the same animal as the orca seen earlier near Alaska. However, there are convincing arguments that "Iceberg" and the Alaskan white orca are actually two different individuals.
    First, although all the photographs made during the sightings show very light-colored animals, the orca seen in Alaska appears to be just slightly darker than "Iceberg" . Such difference in coloration suggests that these were two distinct animals that were independently sighted in the northern Pacific.
    Second, the sightings were very far apart. The Alaskan orca was seen near the central Aleutian Islands, a long string of islands that extends westward from the mainland of Alaska. "Iceberg" was seen near the Commander Islands, off the coast of Russia. More than 1,500 kilometers separate the two locations. Typically, orcas tend to stay near the mainland coast and not travel such a long distance.
    Third, when scientists saw the Alaskan white orca in 2000, they estimated that it was around 20 years old, based on the size of its dorsal (back) fin. When researchers saw "Iceberg" , their estimate of its age, based on the fin size, was also around 20 years—but that was in 2010, when the Alaskan orca would have been 30! The estimates again suggest quite strongly that these are two different individuals.
    Now listen to part of a lecture on the topic you just read about.
    Summarize the points made in the lecture, being sure to explain how they respond to the specific arguments presented in the reading passage.
Despite what the reading says, it’s perfectly possible that the white orca called "Iceberg" by Russian scientists is in fact the same individual that was spotted earlier near Alaska.
    For one thing, the exact color of an Orca’s skin can change a bit from season to season. The reason for this is algae. Algae are small plant organisms that grow on whale skin during some parts of the year. Algae growth would make white skin look a bit darker. The Alaskan sighting occurred during a different season than the Russian sighting, so if we take into account the seasonal variation in algae growth, it could’ve been the same whale seen both times, only one time it was covered with more algae than the other time.
    Second, about the distance problem… it’s important to know that Orcas live in groups that have different lifestyles. Some groups hunt mammals, while other groups hunt fish. The mammal-eating Orcas tend to stay near coastlines and not migrate far, just like the reading said. However, scientists have determined that "Iceberg" belongs to a fish-hunting group. Fish-hunting Orcas follow migrating fish and can travel over 2,000 kilometers in the open ocean, so it wouldn’t have been unusual for "Iceberg" to travel between Alaska and Russia.
    Third, age estimates based on the size of the dorsal fin are not necessarily accurate. You see, after an Orca reaches 20 years of age, its dorsal fin doesn’t grow anymore. So when scientists see an Orca with a fully grown dorsal fin, that Orca could be 20 years old, but it could also be 25 or 30 years old. So "Iceberg" could easily have been older than the scientists estimated, which means it could’ve been the same Orca as the one seen in Alaska earlier.

选项

答案     In 2000 and 2010, two white orcas occurred off the coast of Alaska as well as Russia’s, and the latter one was named "Iceberg”. Some scientists believe that these two orcas are different individuals. The reading passage gives three reasons to support this argument, but the lecturer rebuts them all.
    Firstly, as the reading passage contends, the difference in coloration of the two orcas indicates that they are two distinct individuals. But the lecturer said the difference may have been caused by algae, plant organisms that grow on orcas’ skin during some parts of the year. Considering the seasonal variation in algea growth, the skin color of the same orca may change.
    Secondly, the reading passage emphasizes the long distance between the locations of the two sightings. It suggests that orcas, which tend to stay near the mainland coast, would not travel that far. However, since scientists have determined that "Iceberg" is a fish-hunting orca that will follow migrating fish to the open sea, the lecturer argues that it is possible for "Iceberg" to travel between Alaska and Russia during the decade.
    Finally, based on the size of the dorsal fin, both orcas were estimated to be at the age of 20. If the two orcas were both "Iceberg" , as argued in the reading passage, the one seen off the coast of Russia should have grown to 30 years old in 2010. The lecturer doubts the accuracy of age estimates. After 20, the back fin of an orca stops growing, and thus, "Iceberg" , with a fully grown back fin, could have been over 20 when it was spotted in 2010.

解析     题目:看电影或者看书比体育锻炼更能让人放松。
    本题属于“Agree or Disagree”的类型,考生应在第一段表明同意与否,不建议采取模棱两可的态度。如果选择同意,要强调看电影或者看书对于放松身心的重要意义,反之亦然。在主体部分,考生可以结合人们的生活方式,讨论自己认同的做法有何具体益处。此外,采取欲抑先扬的写法,即先正视和肯定另一种做法的明显优势,再挖掘它的相对劣势,可以增强文章的客观性和全面性。
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