Now listen carefully and answer questions 31—35.
请仔细听并回答问题31—35。
The black bear or Ursus americanus has a wide range in habiting forest area of North America including Canada, the United States and parts of northern Mexico.
黑熊或者美洲黑熊在北美洲拥有广袤的森林栖息地，包括加拿大、美国和北墨西哥的部分地区。
Black bears are omnivorous, getting their nutrition from a wide variety of plants and animals.
黑熊是杂食动物，以多种植物和动物为食获取所需营养。
The particular food any one bear eats depends on what's available in the area where that bear lives as well as on the season of the year.
一只熊具体会吃些什么取决于它在居住的地区内能够找到什么，以及当季都有什么食物。
Generally speaking, plant foods make up 90% of the bear's diet. The rest of its meals consists of animal foods, such as insects and fish.
一般来说，植物占了黑熊食谱的百分之九十，剩下的食物来源是像昆虫和鱼这样的动物。
Bears have a relatively long gestation period. Mating takes place in the spring or early summer.
熊的妊娠期相对来说较长，它们一般在春天或夏初交配。
But bear cubs are born in the following winter. Usually, two cubs are born at a time.
但是幼熊要到冬天才能出生。通常，母熊一胎会生出两只小熊。
Although some litters may have as many as five cubs.
不过也有一些母熊也许一胎最多会生出五只小熊。
Bear cubs are depended on their mother, and may stay with her for close to two years, while black bears can live as long as 25 years.
小熊非常依赖它们的母亲，可能会待在母熊身边将近两年。
They'll live as long as 30 years or more in captivity.
野生黑熊最长能活25年，人工驯养的黑熊可以活到30年，甚至更久。
Now listen carefully and answer questions 36—40.
请仔细听并回答问题36—40。
Much of the black bears range coincides with the range of its close cousin, the grizzly bear.
黑熊栖息地的范围有很大一部分和它的近亲灰熊的栖息地重合。
Although these bears are somewhat similar in the appearance and habits, it isn't difficult to tell the difference between them.
虽然这两种熊在外形和生活习惯方面多少有些相似，但是要区分它们并不困难。
Color isn't necessarily a distinguishing characteristic.
通过颜色特征并不一定能区分它们。
As both species of bears are current a range of colors from almost blonde to dark brown or black.
因为这两种熊目前的颜色都处于金黄到深棕或黑色的范围内。
Many black bears, however, have a patch of fur on their chests that lightening color than the rest of the fur.
不过，黑熊胸前有一簇毛发，颜色比身体其他地方的毛发颜色要浅一些。
Grizzly bears don't have this patch. Size isn't always the distinguishing feature either.
灰熊就没有这簇毛发。身材尺寸经常也不能作为区分它们的特征。
Although grizzly bears are usually heavier with an average weight of 225 kilos.
虽然灰熊通常都更重一些，平均体重可达225千克。
Black bears average are 140 kilos in weight. Grizzly bears spend time digging in the ground for roots and tubers that make up part of their diet.
而黑熊的平均体重只有140千克。灰熊会花很长时间挖出地下的根茎食用。
The large muscles they need for this give them a stick shoulder hump.
它们做这些需要很大的肌肉力量，从而导致它们的肩膀处有一块明显的隆起。
This hump is absent in black bears which don't do the same kind of digging.
而黑熊并不需要做同样的挖掘动作，所以它们的肩膀上并没有这块隆起的部分。
The shape of the face and ears is also different in each species of bears.
这两种熊的面部轮廓和耳朵的形状也是不同的。
Grizzly bears have a depression between the eyes and nose and short round ears.
灰熊眼睛和鼻子之间有一块凹陷的地方，它们的耳朵又短又圆。
Black bears, on the other hand, have a straight profile and longer more pointed ears.
而另一方面，黑熊的面部轮廓更加直挺，耳朵较长较尖。
Grizzly bears are known for their fierce and long sharp claws. Black bears have shorter claws, which are better suited for climbing trees.
众所周知，灰熊十分凶猛，爪子又长又尖；但是黑熊的爪子较短，更加适合爬树。