看绝望的主妇学英语高频短语:Once in a while
Once in a while: Occasionally, sometimes; Sometimes but not very often; From time to time. Synonym: once awhile; now and then; from time to time; occasionally; on occasion; sometimes; at times; now and again.
As in My mom has sweets once in a while but mostly eats only healthy foods.

中文释义:once in a while是偶尔,有时的意思,表示在一段时间里偶尔会做某件事但频率不是很高。比如:My mom has sweets once in a while but mostly eats only healthy foods. (我妈妈偶尔吃点甜食,但大部分都是健康食品。)另外,有很多短语跟它意思相近,例如:once awhile; now and then; from time to time; occasionally; on occasion; sometimes(发生的频率比”once in a while”高); at times; now and again.