A、Leaves. B、Herbs. C、Fruit. D、Human. D黑熊以什么为生?文中在论及到黑熊的生存属性时，这个问题显然是必不可少的，需要考生留心注意。其他三个选项都出现过，只有D)human未提及。

American black bears appear in a variety of colors despite their name. In the eastern part of their range, most of these brown, red, or even yellow coats. (32) To the north, the black bear is actually gray or white in color. Even in the same litter, both brown and black furred bears may be born.
    Black bears are the smallest of all American bears, ranging in length from five to six feet, (33) weighing from three hundred to five hundred pounds.
    Like all bears, the black bear is timid, clumsy, and rarely dangerous, but if attacked, most can climb trees and cover ground at great speeds. When angry or frightened, it is a formidable enemy.
    (34) Black bears feed on leaves, herbs, fruit, berries, insects, fish, and even larger animals. One of the most interesting characteristics of bears is their winter sleep. Unlike squirrels, woodchucks, and many other woodland animals, bears do not actually hibernate (冬眠). Although the bear does not during the winter months, sustaining itself from body fat, its temperature remains almost normal.
    (35) Most black bears live alone, except during mating season. They prefer to live in caves, hollow logs, or dense thickets. A little of one to four cubs is born in January or February after a gestation period of six to nine months, and they remain with their mother until they are fully grown or about one and a half years old. Black bears can live as long as thirty years in the wild, and even longer in game preserves set aside for them.
32. What is the color of the black bear to the north?
33.What is the range of weight of black bears?
34.Which of the following do black bears not feed on according to the passage?
35.When do most black bears live alone?