我从未经历过像那次一样难的期末考试。

I never went through a final exam that was as difficult as that one.

《柯林斯英汉双解大词典》

或许有人会想，“本性难移！”是的，但是独自过圣诞节也是很难熬的。

Somebody's probably thinking, "But change is hard!" Yeah, and so is being alone on Christmas!

youdao

在新千年来临时，当美国报业集团纷纷陷入困境时，我也曾亲见企业经历过的坚难岁月，那段日子里，再大的预算削减、再严格的精简也不算过分。

I had also witnessed the hard times that started to plague most US newspaper companies in the new millennium, during which no budget cut seemed deep enough and no efficiency too grand.

youdao

Well, I talked about the problem of using plasmids in gene therapy, that it's very difficult to get them into cells.

我们之前讨论过,基因治疗中运用质粒的问题,质粒本身极难进入细胞

耶鲁公开课 - 生物医学工程探索课程节选

Because it's hard when you go back being part of any group. Once you are in that group, and away from other people, it's very hard to remember We've talked that -Oh, have you?

因为如果你回到原来的群体中,就会变得难了，因为你只要一呆在那个群体中，远离其他人，就很难,我们聊过这个，-是吗？

普林斯顿公开课 - 人性课程节选

I assume that those problems are not that difficult and I've given you a lot of practice.

我知道这些题目没那么难,我已经让你们练过不少次了

耶鲁公开课 - 基础物理课程节选