冰河世纪

It's a strange and unfamiliar world of islands and mountains that's never been seen by humans.

这是个陌生和新奇的岛屿和山脉 人类从未见过

We may take it for granted that snow and ice are very much part of our world

我们把冰和雪视为世界当然的一部分

and that glaciers and ice sheets seem to be a permanent feature of the landscape

冰川和冰原是永久不解冻的风景

but in fact, nothing could be further from the truth.

但是，实际上，事实并非如此

As far as Earth is concerned, ice is pretty unusual.

当地球被研究以来，冰就是非常特别的

For most of our planet's long history, about 90% of it.

我们地球漫长的历史中有90%的时间

there's been virtually no ice at all.

是一点冰都没有的

Even the dinosaurs that hung around for 200 million years

甚至在恐龙遍地的两亿年前

never saw anything like this.

也没见过这一景象

Our current era is actually an unusual time in Earth's history.

我们处于一个非常时段

It's called an ice age,

所谓的冰河世纪

an era when ice sheets covered large areas of the planet.

当冰川覆盖大片土地时

It began around three million years ago.

大约三百万年前开始

when the continents of North and South America collided.

南北美洲大陆冲撞

The result 3 warm ocean current that flowed around the equator was cut off.

结果，三条沿着赤道流动的海洋暖流被切断

so now the warm water travelled north.

所以这暖流现在流向北方

Today we know this current as the Gulf Stream.

就是我们今天熟悉的墨西哥湾流

重点讲解

1、permanent

永久的；永恒的

Heavy drinking can cause permanent damage to the brain.

酗酒能造成永久性大脑损伤。

a permanent solution to the problem...

该问题一劳永逸的解决办法

（尤指问题或困难）不断出现的，一直存在的

a permanent state of tension.

长久以来的紧张局势

They feel under permanent threat.

他们觉得一直处于威胁之下。

（家庭住址）固定的

York Cottage was as near to a permanent home as the children knew.

在孩子们眼中,约克小屋最像一个安定的家。

They had no permanent address.

他们没有固定居所。

2、collide

碰撞;相撞;撞上

Two trains collided head-on in north-eastern Germany early this morning.

今天早上德国东北部两列火车迎面相撞。

Racing up the stairs, he almost collided with Daisy.

他飞奔上楼，差点撞到黛西。

(目标、意见等)冲突，抵触

The aims of the negotiators in New York again seem likely to collide with the aims of the warriors in the field.

看来，纽约谈判人员的目标可能会再次与战场上勇士们的目标发生冲突。

In the next two years, Nasser regularly collided with the different Western powers, who refused to arm him.

随后的两年里，纳赛尔不断与拒绝为他提供武器装备的几个西方大国发生冲突。

3、current

(河、湖或海的)水流，潮流

Under normal conditions, the ocean currents of the tropical Pacific travel from east to west.

在正常情况下，太平洋的热带洋流自东向西流。

The couple were swept away by the strong current.

这对夫妻被巨大的水流卷走了。

现时的;当前的;进行中的

The current situation is very different to that in 1990.

当前的形势与1990年截然不同。

He plans to repeal a number of current policies.

他计划废除一些当前的政策。