They had to keep the herd together day and night and protect it from bad men and Indians.

VOA: special.2010.03.18

It's about the four-dollar cup of coffee that we have three times a day, because we need to keep the feel going.

可能只是节省一杯4美元的咖啡,我们每天要喝三次咖啡，只是为了留住这种感觉。

普林斯顿公开课 - 人性课程节选

He sometimes used 9 containers of writing fluid a day to keep such detailed records.

VOA: special.2009.01.24

The next day, at their school, the woman asks the man to keep an eye on, or watch the young students in her class while she is out of the classroom.

VOA: special.2009.09.06