It would be much better to get rid of her once and for all.

Then she saw that strange look of his once again.

He had to get rid of her once and for all.

She slept there on an average of about once a month.

He lost on an average of once every twenty minutes.

But at least I know that he has to be reminded of her once a week.

I guess it comes out to an average of about once a month.

That would be an extra £250 or so a year (average of once a week).

"Everybody needs to be made fun of once in a while."