"He was young and I had a very good time drawing his picture because I used a lot of reference material that were paintings made of him at different times in his life.

VOA: special.2009.02.27

I'll say more about this next time with reference to Yeats's late poetry.

下次我会多谈些这方面的,关于叶芝晚期诗歌的内容。

耶鲁公开课 - 现代诗歌课程节选

Undefined reference, what was the solution last time?

未定义的引用，上次我们是怎么解决的呢？

哈佛公开课 - 计算机科学课程节选

This is the first time we have such a reference.

这是我们首次遇到这类的参考文献

耶鲁公开课 - 古希腊历史简介课程节选

Second formula tries to relate the final velocity of some time, t, to the initial velocity and the distance traveled with no reference to time.

第二个式子能把某段时间t的末速度,和初速度,经过的路程联系在一起,并且不引入时间

耶鲁公开课 - 基础物理课程节选