I met him only the once, and that was enough.

我只见过他一次，那就够了。

《柯林斯英汉双解大词典》

She always writes me once a month, if only to scold me because I haven't answered her last letter yet.

她总是一个月写一封信给我，即使仅仅是为了责备我还没有回她的上一封信。

《柯林斯英汉双解大词典》

I say you only live once and we work hard and what's the point if you can't go on holiday.

我觉得你就只活一次，我们努力工作，如果不能去度假的话生活又有什么意义呢？

youdao

One visitor,a former Navy man,once said: "The only good thing about my fighting in the war was that I was too young to be terrified."

VOA: special.2009.05.25

One, two, three, four, so on each level of the picture I'm drawing, I've seem only to be looking at each number once.

，2，3，4，可见，在我画的,这幅图的每一层上，对每个数字,都只会用到一次。

哈佛公开课 - 计算机科学课程节选

Pretty much I think about it only once a year, when I'm giving this very lecture.

最多是一年想一次，当我要上这节课时。

耶鲁公开课 - 死亡课程节选

Even if I only visit once or twice a year, I enjoy supporting an institution that has filtered through so many of my dreams.

FORBES: A Very Boozy Night At The Museum

My father, who I barely knew -- I only met once for a month in my entire life -- was said to be a non-believer throughout his life.

WHITEHOUSE: National Prayer Breakfast

Rather than anticipate the break, I decided to play the move as a reactionary trader, adding shares only once I saw the break transpire.

FORBES: A Trading Lesson in Tupperware