Philosophy is hard stuff to read.

哲学是很难读懂的东西。

耶鲁公开课 - 死亡课程节选

It's hard to write a lot of stuff in a language that you're not as familiar with,

用你不熟悉的语言写论文真的很难，

选择国际学的理由 - SpeakingMax英语口语达人

This is different from the hard disk, which is where files and stuff are permanently stored.

这个和硬盘是不一样的，那是存储,文件之类的东西的。

哈佛公开课 - 计算机科学课程节选

It's really hard to think of all stuff off the top of my head.

脑子里一时想到的都说出来还真难呢。

只要是音乐就好 - SpeakingMax英语口语达人

It was hard to piece all of this stuff together.

这个解释稍微有点难理解

耶鲁公开课 - 欧洲文明课程节选