keep track of

1.

Keep track of the time you actually travel.

把你旅行的实际时间记录下来。

2.

Please ask if you cannot keep track of what I'm telling you.

如果你们听不懂我所讲的话，请提问。

3.

As a doctor James has to keep track of the latest developments in medicine.

作为一名医生，詹姆斯必须了解医学的最新发展动态。

4.

I know that the professor will keep track of my attendance but that I will not have to do any papers or take any exam.

我知道教授会记录我的出勤情况，并且也知道我不用写论文或者参加考试。