Marsha, these are letters to my family and friends back at home......four letters!

玛莎，这些给我家乡的亲友的信件......四信！

Four letters in three months and this is the first mention of Kathleen Johns?

三个月来四信 这第一凯萨琳琼斯的？

They've got a repeating four- letter word ending with two symbols that stand for L.

现在他们找好几个两个一样符号的 四个字的字。

I heard that the last four letters were dubba-you, ex, why, zee.

我听最后四个字dubba-you，ex，why，zee。

The code comes out to be a fairly simple alphabet, four letters: A, T, C and G.

这个遗传密码简单的字表组成，四个字，A，T，C和G （碱基）。

Sometimes three or four letters together can make one sound.

有时三个或四个字在一起可以发出一个声音。

Imagine what it would be like if the English alphabet had four letters.

想象一下， 如果英文字表有四个字什么样子。

Don’t get me too excited because I use four letter words when I get excited.

不要让我太兴奋， 因为当我兴奋时我使用四个字的单词。

And it's just a cool four letter word.

这只一个很酷的四个字单词。

Can you fit that into your four letter code?

你能把它放入你的四字代码中吗？

So all life on this planet is made in ATCGs, the four letters of DNA.

所以这个星球上的所有生命都 ATCG 构成的，即 DNA 的四个字。

Ziggy had scrawled four letters across the page.

齐吉在页面上涂鸦了四个字。

Hey, what's a four- letter word for cut?

嘿, 什么四字的切割词?

" Fast" has four letters and four sounds.

“快”有四个字和四个声音。

We also have another radio station, called " KNBC." Usually radio and television stations have four letters.

我们还有另一个广播电台，叫做“KNBC” 。 通常电台和电视台有四个字。

Part four: letters and sounds are not always the same thing.

第四部分：字和发音并不总一回事。

It was too simple. It had just four basic components, called nucleotides, which was like having an alphabet of just four letters.

它太简单了，主要4个被称为核苷酸的基本物质组成。这就好比一个只有4个字的字表。

And then we hear it's on City Road, then the road to the right and we see three, oh actually four letters there.

然后我们听它在城市路，然后路的右侧，我们看三个，哦，实际上四个字。

The call signs in the U.S. all have four letters for the radio and TV stations, or almost all of them.

美国的呼号都广播电台和电视台的四个字， 或者几乎全部。

After I was able to make four letters, I would tell any boy who could write that I could write as well as he did.

在能够写出四个字后，我便告诉任何一个写字的男孩，说我能写得和他一样好。