英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—12

 They continually chatter¹ away to each other. It's all about keeping aggression² under control.

 

Their massive claws rake the skin like knives, cutting it into strips. 

 

At two years old, this bear is testing his status, standing³ up to other bears. Sharing food helps everyone survive in an environment where prey⁴ is usually hard to come by. 

 

As summer progresses, the temperature creeps above freezing and the larger ice sheets fragment into ever smaller plates. To avoid being trapped on shrinking ice floes, the cubs⁵ must get used to an endless polar assault course.

 

Rolling is clearly fun, but it also has a purpose. It squeezes out water trapped in the fur. Her cubs are growing fast and are full of energy.  But to keep them fit, she must keep them fed. A male has killed a bearded seal. For the sake of her cubs, she needs to be cautious. Burying the carcass will help reduce its odor, concealing⁶ it from other bears.

1 chatter   

vi.／n.喋喋不休；短促尖叫；(牙齿)打战

参考例句：

• Her continuous chatter vexes me.她的喋喋不休使我烦透了。
• I've had enough of their continual chatter.我已厌烦了他们喋喋不休的闲谈。

2 aggression   

n.进攻，侵略，侵犯，侵害

参考例句：

• So long as we are firmly united, we need fear no aggression.只要我们紧密地团结，就不必惧怕外来侵略。
• Her view is that aggression is part of human nature.她认为攻击性是人类本性的一部份。

3 standing   

n.持续，地位；adj.永久的，不动的，直立的，不流动的

参考例句：

• After the earthquake only a few houses were left standing.地震过后只有几幢房屋还立着。
• They're standing out against any change in the law.他们坚决反对对法律做任何修改。

4 prey   

n.被掠食者，牺牲者，掠食；v.捕食，掠夺，折磨

参考例句：

• Stronger animals prey on weaker ones.弱肉强食。
• The lion was hunting for its prey.狮子在寻找猎物。

5 cubs   

n.幼小的兽，不懂规矩的年轻人( cub的名词复数 )

参考例句：

• a lioness guarding her cubs 守护幼崽的母狮
• Lion cubs depend on their mother to feed them. 狮子的幼仔依靠母狮喂养。 来自《简明英汉词典》

6 concealing   

v.隐藏，隐瞒，遮住( conceal的现在分词 )

参考例句：

• Despite his outward display of friendliness, I sensed he was concealing something. 尽管他表现得友善，我还是感觉到他有所隐瞒。 来自《简明英汉词典》
• SHE WAS BREAKING THE COMPACT, AND CONCEALING IT FROM HIM. 她违反了他们之间的约定，还把他蒙在鼓里。 来自英汉文学 - 三万元遗产