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Now listen carefully and answer questions 31—35.
請仔細(xì)聽并回答問題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擁有廣袤的森林棲息地，包括加拿大、美國和北墨西哥的部分地區(qū)。
Black bears are omnivorous, getting their nutrition from a wide variety of plants and animals.
黑熊是雜食動物，以多種植物和動物為食獲取所需營養(yǎng)。
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.
一只熊具體會吃些什么取決于它在居住的地區(qū)內(nèi)能夠找到什么，以及當(dāng)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.
一般來說，植物占了黑熊食譜的百分之九十，剩下的食物來源是像昆蟲和魚這樣的動物。
Bears have a relatively long gestation period. Mating takes place in the spring or early summer.
熊的妊娠期相對來說較長，它們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，母熊一胎會生出兩只小熊。
Although some litters may have as many as five cubs.
不過也有一些母熊也許一胎最多會生出五只小熊。
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.
小熊非常依賴它們的母親，可能會待在母熊身邊將近兩年。
They'll live as long as 30 years or more in captivity.
野生黑熊最長能活25年，人工馴養(yǎng)的黑熊可以活到30年，甚至更久。
Now listen carefully and answer questions 36—40.
請仔細(xì)聽并回答問題36—40。
Much of the black bears range coincides with the range of its close cousin, the grizzly bear.
黑熊棲息地的范圍有很大一部分和它的近親灰熊的棲息地重合。
Although these bears are somewhat similar in the appearance and habits, it isn't difficult to tell the difference between them.
雖然這兩種熊在外形和生活習(xí)慣方面多少有些相似，但是要區(qū)分它們并不困難。
Color isn't necessarily a distinguishing characteristic.
通過顏色特征并不一定能區(qū)分它們。
As both species of bears are current a range of colors from almost blonde to dark brown or black.
因為這兩種熊目前的顏色都處于金黃到深棕或黑色的范圍內(nèi)。
Many black bears, however, have a patch of fur on their chests that lightening color than the rest of the fur.
不過，黑熊胸前有一簇毛發(fā)，顏色比身體其他地方的毛發(fā)顏色要淺一些。
Grizzly bears don't have this patch. Size isn't always the distinguishing feature either.
灰熊就沒有這簇毛發(fā)。身材尺寸經(jīng)常也不能作為區(qū)分它們的特征。
Although grizzly bears are usually heavier with an average weight of 225 kilos.
雖然灰熊通常都更重一些，平均體重可達(dá)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.
而黑熊的平均體重只有140千克。灰熊會花很長時間挖出地下的根莖食用。
The large muscles they need for this give them a stick shoulder hump.
它們做這些需要很大的肌肉力量，從而導(dǎo)致它們的肩膀處有一塊明顯的隆起。
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樣的挖掘動作，所以它們的肩膀上并沒有這塊隆起的部分。
The shape of the face and ears is also different in each species of bears.
這兩種熊的面部輪廓和耳朵的形狀也是不同的。
Grizzly bears have a depression between the eyes and nose and short round ears.
灰熊眼睛和鼻子之間有一塊凹陷的地方，它們的耳朵又短又圓。
Black bears, on the other hand, have a straight profile and longer more pointed ears.
而另一方面，黑熊的面部輪廓更加直挺，耳朵較長較尖。
Grizzly bears are known for their fierce and long sharp claws. Black bears have shorter claws, which are better suited for climbing trees.
眾所周知，灰熊十分兇猛，爪子又長又尖；但是黑熊的爪子較短，更加適合爬樹。
