快点学这三个字母，这样你就不用去了！

Hurry up and learn the three letters, then you won't have to go!

youdao

你选择的旋转字母的数量就是我们在密码学中所说的密匙。

The number that you choose to rotate your letters by is what we call in cryptography, a key.

youdao

经济学论文联合作者，也是按照姓氏首字母靠前的学者姓名排列。

Joint authors of economic papers are listed under the name that falls first in the alphabet.

youdao

It's not a simple matter. Imagine what it would be like if you had to learn about sixty such things?

绝不是个简单的事,想象一下如果你得学,六十个字母会是什么状况

耶鲁公开课 - 古希腊历史简介课程节选

The number that you choose to rotate your letters by is what we call in cryptography, a key.

你选择的旋转字母的数量,就是所谓的加密学，一个密钥。

哈佛公开课 - 计算机科学课程节选