"And keep a close eye on them at all times."

The students must keep the document with them at all times.

That he kept the plans upon him at all times.

Here was his journal, that he kept with him at all times.

Which I was keeping with me at all times, by the way.

You have to keep a close eye on him at all times.

In future he would keep those instruments with him at all times.

It is supposed to be kept with the hair and at all times.

Parents need to keep an eye on their children at all times.

They had to keep ahead of their enemies at all times.