Teachers often correct students who write once in awhile, explaining that it's a misspelling of once in a while.

She remembered him, once and away, as if through a half-forgotten dream.

Not even once— I wouldn't touch that fad with a ten-foot pole.

We stopped at Once Brewed to rest in a small tea room before continuing our walk along Hadrian's Wall.

I try to clean out my closet once and a while, but it never stays organized.

Legends say that once upon a time a great storm shaped the coastline we know today.

I visit my hometown once in a blue moon, usually only for special family events.

I treat myself to a slice of cake every once in a while to celebrate small victories.

Alright team, once more into the breach — we have a deadline to meet and no time to waste.

She goes to the theater once in a purple moon, when she finds a free evening.