听力文本

If surprise fails, there will be a chase.
一旦突袭失败，鲨鱼就会展开追击
The shark is faster on a straight course
鲨鱼的直线速度更快
but it can't turn as sharply as the seal, its agility versus power
但是转向却不如海豹灵活，这是敏捷与力量的对抗
Once the seals have finished breeding, the giant sharks will move on.
等到海豹结束繁殖，大白鲨便会继续前进

It's now becoming clear that great whites migrate thousands of miles across the oceans
可以肯定的是，大白鲨长途跋涉数千英里横越大洋
to harvest seasonal abundances in different seas.
就是为了在不同海域享用这种季节性的盛宴。
The sun, beating down on tropical waters, powers the weather systems of the globe.
太阳烘晒着热带地区的海水，驱动了全球天气系统
Moisture evaporates from the warming ocean and rises to create great storms.
海水受热蒸发成水蒸气，上升并形成巨大的风暴。

词汇解析

1.on a straight course 直线
He made an effort to think of nothing but the problem of keeping the jeep on a straight course.
他竭力控制自己不去思索，集中精力让吉普沿笔直方向行驶。

2.move on 继续前进
He should move on and stop moaning about the injustice of it all.
他应该立即停止抱怨所有的不公, 继续前进.

3.beat down on 烘晒着
The July sun beat down on them.
7月的骄阳火辣辣地照晒着他们。

视频及简介

北极的春季，北极熊妈妈和它的孩子从它们的洞穴中走出来，它们只有短短的两周时间，它们要在冰雪融化前穿越冰冻的大海，它们进退两难。在这集中，我们将看到一些最难得的、完整的北极熊生活的画面。