The Public Utilities Commission inspects us once a year.

公用设施委员会每年到我们这里视察一次。

《柯林斯英汉双解大词典》

He cleans his car once a week.

他每周洗一次汽车。

《牛津词典》

He comes to see us once a week.

他每周来看望我们一次。

《牛津词典》

There is literally concrete evidence of their work." Tony Hawk says skateboarding was once a sport on the edge of society.

VOA: special.2009.09.11

By the way, once again there's a bit of a rift there between Barthes and Foucault. Foucault wouldn't say "quite futile."

顺便说一句，这里巴特和福柯,又有了分歧，巴特不会说“没有希望“

耶鲁公开课 - 文学理论导论课程节选

and the last quarter is a seminar in which you only go once a week for three hours

最后一个季度是研讨会，每周只需要参加三个小时，

群集课程 - SpeakingMax英语口语达人

One can see that this was once a vibrant city with an active commercial class.

FORBES: We've Seen This Movie Before

Actually, by suggesting I think about death once a day, Ura was going easy on me.

BBC: Bhutan��s dark secret to happiness

Once a woebegone district characterised by criminal activity and crumbling architecture, Getsemani is undergoing a 21st-century renaissance.

BBC: A renaissance beyond Cartagena��s historic walls