Alex rooms with Henry Thorpe, and since Henry is one of the senior prefects, he would know for sure.

阿列克斯和亨利·骚伯同屋，而亨利是四年级级长之一，他准知道。

youdao

As the founder of Facebook, you would have thought he would know how to update his relationship status.

作为Facebook的创始人，他应该知道如何更新自己的“感情状态”，至少人们会这么认为。

youdao

So, if Dr Clark could determine the mass of another star in the cluster he would know that the mass of the star that begat the magnetar must have been bigger.

而因为恒星的寿命是和质量成反比，所以，如果Clark博士能够确定星团中另外一颗恒星的质量，那么他就可以得出产生磁星的恒星质量必定更大的结论。

youdao

In other words, he would know what the children are doing even when he is not watching them.

VOA: special.2009.09.06

If he had read as much, he would know as little.

如果他读得很多，却知道得很少。

耶鲁公开课 - 政治哲学导论课程节选

Sure, if my son would wake up and I didn't tell him, he wouldn't know that it was duplicate.

当然，如果我儿子醒来,可我还是没告诉他，他不会知道这塔是重新搭的。

耶鲁公开课 - 死亡课程节选

They believe he was the one who wrote it because there were details in it only he would know.

NPR: Massive Manhunt On For Ex-Cop Accused Of Killing 3

He would know it because he once lived it, and he fixed it.

FORBES: Ronald Reagan Would Not Be Fooled By Today's Presumptions of Low Inflation

You might note that Mr. Mohamed was a certified appraiser so you might think he would know what to do.

FORBES: No Appraisal No $18.5M Deduction, Says Tax Court