英语四级听力练习材料：熊的生活
Female bears have yet another reason for chowing down during the summertime. Although bears mate in the spring, the fertilized eggs don’t begin to develop until the females return to the den for the winter. The females must have stored up enough fat over the summer to support themselves and their developing cubs over the long winter. If not enough fat is stored, the embryos won’t develop at all, and the female bear won’t produce any cubs that year.
Like Yogi Bear, real bears also seek out humans who might be carrying a snack, and many bears look for garbage, pet food, livestock, and campers for an easy supply of food.
Contrary to popular belief, bears don’t eat humans. Unless humans surprise the bear or threaten the cubs, bears will avoid human contact. They really are more interested in your picnic basket.
熊的真实生活是怎样的
在电影“森林王子”中，熊巴鲁成天都在唱歌、跳舞和咀嚼番木瓜。
四级听力练习
实际上，除了唱歌和跳舞的局部，这是对现实中的熊最真实的写照。
北美熊也会用一整个夏天来觅食。
甚至像Yogi和Balloo这样的卡通熊都知道，吃是件很重要的事情。熊必需要在食物充足的夏季摄取足够的脂肪来度过冬眠期，那时，储存的脂肪将是熊获得能量的主要来源。
黑熊和灰熊属于杂食动物，既吃肉也吃素。一般的熊多食坚果、浆果及蔬菜类食物，但它们也爱吃昆虫、鱼和小型哺乳动物。
雌雄在夏天觅食还有另一个缘由。虽然熊在夏天交配，但受精卵要等到冬天雌熊回到地窖才会开头发育。雌熊必需要在夏季储存足够的脂肪来帮忙自己和正在发育的幼仔度过冬天。假如储存的脂肪不够多，胚胎就不会发育完全，雌熊当年将不会产下任何幼仔。
现实中的熊像Yogi一样也会去查携带零食的人类。许多熊为了觅食更加简单，它们会去查垃圾、宠物粮、家畜和野营者来猎取食物。
熊其实并不会像一般人所想的那样会吃人。它们会尽量避开和人类接触，除非是受到惊吓或者幼仔受到威逼。事实上，它们对你的野餐篮更有兴趣。