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By the time a child is five,
到孩子五岁的时候
they'll know as many as 5,000 words.
他们可以识得五千个单词
My voice changes when I get in a situation.
当我进入不同状态时 声音就会改变
That requires a rather precise placement of the tip of the tongue.
这需要舌尖位置相当精准的变化
At the third stroke the time will be five...
第三次报时的时间是五点
Language is exclusively human
语言是人类所特有的
and it's something that comes naturally to us.
也是每个人与生俱来的
...from their voice,
通过他们的声音
so it's clear the voice is deeply expressive.
显然声音相当具有表现力
Despite decades of intense investigation,
尽管经过了数十年紧锣密鼓的调查研究
we still know very little about the basic origins of language.
对语言的主要起源我们仍然知之甚少
Sunlight.
阳光
While other creatures can communicate
其它的动物可以
their basic needs and emotions to each other,
彼此交流基本需要和情绪
we're the only species
而我们是唯一
that can convey complex meaning and thought.
可以传递复杂内涵和思想的物种
T or the D at the end of a word for, say, dot or dog.
以T或D结尾的单词 比如Dot或Dog

重点解释

While other creatures can communicate their basic needs and emotions to each other,其它的动物可以彼此交流基本需要和情绪

each other互相；各自

The two plans meshed with each other smoothly.

这两个计划互相配合得很好。

The pupils sneaked on each other to the teacher.

学生相互向老师讲了我的坏话。

they'll know as many as 5,000 words.他们可以识得五千个单词

as many as和 ... 一样多

As many as 500 workers work on the farm.

在这个农厂干活的工人多达500人。

As many as 100 people were killed in the air crash.

这次空难中多达一百人丧生。

相关短语as many again加倍

I have books as many again as you.

我的书比你的多一倍。

There were half as many again as there were last time.

只有上次一倍半的量。