Some critics think Mark Twain's later works were more serious because of his sadness.

VOA: special.2010.03.21

I have no idea what's here at the moment so I'm just going to draw a question mark because that memory might have been used previously for some other purpose, but we know it's currently available to us so we have four bytes of memory.

我不知道在此刻这里是什么,所以我画一个问号，因为那块内存可能在之前,为其它的目的而使用过，但是我们知道它可以为我们所使用,这样我们就有4个字节的内存。

哈佛公开课 - 计算机科学课程节选

And so part of the wilderness experience for me I think Mark Twain talks about wilderness and he says, I do it chiefly because it is difficult.

对于我来说，荒野的经验就像是,马克吐温在谈到荒野时所说，因为困难，所以我才去做。

普林斯顿公开课 - 人性课程节选

But because she was otherwise so perfect, he found the mark had become unbearable.

VOA: special.2009.09.26

Because at the end it turned out that Mark Antony and Octavian fought a civil war.

因为最终马克·安东尼与屋大维,展开了内战。

耶鲁公开课 - 新约课程节选

Well, this question mark becomes an O, this question mark becomes an O, and then the loop terminates 0 1 2 because it's iterating from zero to N so that's zero, 1, 2 and the length of the string is 3 so the loop terminates, but I remember that I needed to have this special sentinel value so I'm just going to put it there manually.

嗯，这个问号变成了，这个问号变成了0，然后循环结束了,以为迭代从0到N，那就是，字符串的长度是3，然后循环就结束了，但是我记得我需要这个特殊的标记值,所以需要手动的加上它。

哈佛公开课 - 计算机科学课程节选