They've probably all slept with each other at least once.

I have slept with most of them at least once.

Well, she deserved to sleep late every once in a while too.

Many people have trouble sleeping once in a while, especially if they are getting used to a new work shift.

It was bad knowing that he had once slept in this bed.

"You ought to sleep once in a while," he said.

Are you really upset because I sleep with other men once in a while?

Even if he slept with her only once, she could expect rich presents.

If they once sleep in that grass, no harm can hurt them more.

"I once slept 78 years and still was collected by my original ship."