既然不是这样，我想我必须这样做。

Since that is not so, I suppose I must do it.

youdao

我必须这样做——尽管我不知道为什么。

I must—though I don't know why.

youdao

为了自己，我必须这样做。

I must do this for myself.

youdao

Now, in that Northern society and here we're using labels pretty loosely, but so be it the northern states; and well I'll leave the outline up for the moment. No I won't.

现在,在北方社会,现在我们标记做得很散,但必须这样,北方的州,我呆会会给你们一个大纲,但不是现在

耶鲁公开课 - 美国内战与重建课程节选