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For a pet who's been around so long,
对于一个围绕在人们身边的宠物
dog research is an astonishing new area of science.
狗类的研究是令人惊奇的科技新领域
It's a very basic human need to have social relationships.
而对于人类来说　社交关系是基本需求
One of these wonderful things about dogs, of course,
当然　关于狗狗最奇妙的事之一
is they offer you a way of giving unconditional love
是它们能给你无条件的爱
and receiving unconditional love in the other end.
而且另一方面也无条件的接受你的爱
Dogs are the ones that live with us in the same enviornment
狗狗和我们生活在相同的环境
and they're selected to live in this new enviornment
它们被挑选出来在新的环境中生活
and they're specially tunned into human.
它们特别适应人类
So human are their natural social partner.
自然而然的 它们就成了人类的伙伴
But we are only beginning to recognize their full potential.
然而我们才发掘出它们身上潜能一小部分
Understanding dogs has the capacity
通过对狗狗的进一步研究让我们有能力
to give us insights into disease,
更加深刻的了解人类的疾病
the human mind and our varier existence.
人类的内心世界以及我们丰富多彩的生活
I think one reason that there're almost 7 billion people on earth
我想地球上有几乎70亿的人口的原因
is in large part due to the roles the dogs have played
很大程度上也是基于狗狗
in our evolutionary existence.
在我们进化过程中所扮演的角色
While we can have good relationship with wide variety of animals
人类历史上和很多种类的动物
historically our relationship with dogs
有很好的关系 而我们和狗的关系
seems to be the longest one among any domestic animal.
似乎比任何家畜都长远
Personally I don't think it's any coincidence
以我个人之见 我认为狗狗能成为
the dogs is refered to man's best friend.
人类最好的朋友 并不仅是一种偶然的巧合

重点解释

there're almost 7 billion people on earth is in large part due to the roles the dogs have played in our evolutionary existence.我想地球上有几乎70亿的人口的原因很大程度上也是基于狗狗在我们进化过程中所扮演的角色

due to:因为，由于

Some students quit school due to poverty.

一些学生因贫困而辍学。

Mr.Black bowed out of politics due to poor health.

布莱克先生由于健康不佳而退出政治生涯。

play a role in:在 ... 中起作用； 扮演角色

He was invited to play a role in this TV play.

他被邀请在这个电视剧里扮演一个角色。

we can have good relationship with wide variety of animals historically our relationship with dogs人类历史上和很多种类的动物有很好的关系

variety of:各种的

A great variety of flowers were shown in the park.

公园里展出了很多品种的花。

Personally I don't think it's any coincidence the dogs is refered to man's best friend.以我个人之见我认为狗狗能成为人类最好的朋友并不仅是一种偶然的巧合

refer to:涉及；指的是；提及；参考；适用于

The new law does not refer to land used for farming.

这条新的法律不适用于农用土地。

Don't refer to this matter again, please.

请不要再提这件事了。