【简答题】According to Dr. David, Americans ________. A) are ideally vigorous even under the pressure of life B) often neglect the consequences of sleep deficit C) do not know how to relax themselves properly D...
【简答题】We can infer from Dr. Myers and Dr. Worm’s paper that ________. [A] the stock of large predators in some old fisheries has reduced by 90% [B] there are only half as many fisheries as there were 15 yea...