The Canadian government knew how hard it was to live in the western part of the country.

VOA: special.2009.02.04

We are not really like pinpointing one tradition... This is the part hard to draw lines.

我们并非要一对一地认定传统。,这正是难以区分之处。

普林斯顿公开课 - 人性课程节选

All right. Because we're about to get to the hard part Sigh. All right.

第一层嵌套数组，好，很安静啊,大家有什么问题么？

麻省理工公开课 - 计算机科学及编程导论课程节选

These cells are rare and so it's been hard to identify them, that's part of it.

这些细胞太少了,所以很难找到,这是原因之一

耶鲁公开课 - 生物医学工程探索课程节选

I actually thought it was hard to understand, just what was happening, the action part of the story. It might have been that I read it too quickly. Uh huh. Harder than "Menelaiad" to understand? No.

事实上，我认为它很难理解，就是到底发生了什么，即故事中的动作部分，也可能是我读得太快的缘故,所以不太理解罢，比《梅尼洛斯》更难懂吗，不是的。

耶鲁公开课 - 1945年后的美国小说课程节选

I can only imagine though, at this point in the semester, what will become Milton's eventual championing of marriage is pretty hard to imagine, in part because we're just devoting our second class to a literary work given almost entirely to the virtue of chastity.

然而我只能认为，在学期的这个时候，什么将成为弥尔顿婚姻的最终捍卫者,一定难以想象，一部分是因为,我们的第二节课一直在讨论,关于贞洁的美德的作品。

耶鲁公开课 - 弥尔顿课程节选

In fact, even if you haven't had a biology class it's hard to be alive in 2008 and not know something about DNA; it's become such an important part of our lives.

实际上,即使你们没有上过生物课,也不可能活在当下却对DNA一无所知,它已经与我们的生活密不可分

耶鲁公开课 - 生物医学工程探索课程节选