We had to go and see the principal one at a time.

我们得逐一去见校长。

《牛津词典》

I answered the phone but there was no one at the other end.

我接了电话，但线那头没有人。

《牛津词典》

Introduce foods one at a time and notice if you feel uncomfortable with any of them.

一次尝一种食物，看你是否对其中某种食物感到不适。

《柯林斯英汉双解大词典》

He said gardens like the one at the White House help people reconnect with food and eat more healthfully.

VOA: special.2009.03.31

We've added an extra one at 11:00, an extra one at 2:00, and we've added one at 1:00.

我们在11点钟加了课，还有2点和1点。

麻省理工公开课 - 固态化学导论课程节选

To disfigure the mouth -- this is how I would interpret it -- to disfigure the mouth has a primary effect in rendering one at least temporarily speechless.

把嘴巴丑化--这就是我所理解的-,丑化自己的嘴巴使自己暂时不能说话,它是有十分重要影响的。

耶鲁公开课 - 弥尔顿课程节选

She planted one at the head of the grave and the other at the foot.

BBC: The end of a wandering way of life?

Eight reversible causes have to be checked one at a time before someone is pronounced dead.

BBC: NEWS | UK | Magazine | How do you diagnose death?

The Sainsbury's Summer Series includes two Birmingham meetings and one at the Olympic Park in London.

BBC: Sainsbury's to sponsor British Athletics summer series