英文标志词：explain, reason, account for, provide a rationale for, reconcile the discrepancy/paradox.
读文章方式：不要关心文章的推导过程，只需从文中拎出所要解释的对象说它对即可，用常识解题。
1. 解释结果。
例1. The population of elephant seals, reduced by hunting to perhaps a few dozen animals early in this
century, has soared under federal protection during the last few decades. However, because the
species repopulated itself through extensive inbreeding, it now exhibits a genetic uniformity that is
almost unparalleled in other species of mammals, and thus it is in far
extinct than are most other species.
Given the information in the passage above, which of the following is most likely the reason that
other species of mammals are less likely than elephant seals to become extinct?
(A) Other species of mammals have large populations, so the loss of a few members of the species is not significant.
(B) Other species of mammals have increased their knowledge of dangers though the experience of generation after generation of animals.
(C) In other species of mammals, hunters can readily distinguish between males and females or between young animals and adults.
(D) In other species of mammals, some members of the species are genetically better equipped to withstand a disease or event that destroys other members of the species.
(E) Other species of mammals have retained habits of caution and alertness because they have not been protected as endangered species.
2. 解释矛盾。(注意侧重点)
例2. During the day in Lake Constance, the zoo-plankton D. hyalina departs for the depths where food is
scare and the water cold. D. galeata remains near the warm surface where food is abundant. Even though D. galeata grows and reprocess much faster, its population is often outnumbered by D. hyaline.
Which of the following, if true, would help resolve the apparent paradox presented above?
(A) The number of species of zooplankton living at the lakes is twice that of species living at the surface.
(B) Predators of zooplankton, such as white-fish and perch, live and feed near the surface of the lake during the day.
(C) In order to make the most of scare food resources, D. hyaline matures more slowly than D. galeata.
(D) D. galeata clusters under vegetation during the hottest part of the day to avoid the sun’s rays.
(E) D. galeata produces twice as many offspring per individual in any period of time does D. hyalina.
例3. For the United Stats meat industry, there is good news and bad news. The bad news in that over the
last three years people in the United States have been eating less meat. The good news is that during
this same time period meat producer’s profits have risen steadily.
Which of the following, if true during the last three years, contributes most to a resolution of the
apparent discrepancy above?
(A) People have been eating less meat because they are more health conscious than in the past.
(B) In the United States many new restaurants that specialize in vegetarian meals have opened.
(C) Competition from the growing fish industry has forced meat producers to sell meat at bargain prices in an attempt to attract more consumers.
(D) Countries that are unable to produce enough meat for their populations have become a new and lucrative market for United States meat producers.
Meat producers have invested large amount of money on advertising in order to win back consumers who have decreased their meat consumption.