Three men were arrested and one was under guard in a hospital.

有三人被捕，一人在医院里受到监视。

《柯林斯英汉双解大词典》

One prison guard was killed when a riot broke out in the jail.

一位狱警在监狱骚乱中遇难。

《牛津词典》

One young policeman stood guard outside the locked embassy gates.

一名年轻的警察在大门紧闭的使馆外站岗。

《柯林斯英汉双解大词典》

The Coast Guard Academy can have thirty-five international students at any one time;

VOA: special.2009.06.04

One other very important thing to understand about this defensive problem and this is one of the debatable issues between the old guard and the traditional interpretation; I'm still giving you the traditional view.

对于防御的问题还有另外一个很重要的因素,这也是老顽固们对传统观点,争论的一个话题,我还是采用传统观点的说法

耶鲁公开课 - 古希腊历史简介课程节选

But Congress will be worried that its opponents seem to be uniting round a similar theme: that the party's leaders are too close to America, and cannot be trusted to guard one of India's proudest achievements, an independent nuclear deterrent.

ECONOMIST: India

This changing of the guard is one of the most closely watched exercises in pop culture, especially as it takes place at one of TV's mainstay productions.

CNN: Jay Leno announces 'Tonight Show' exit

In Maryland, the Coast Guard said one man was rescued and two men were missing after a fishing vessel became disabled 15 miles east of Assateague Island.

WSJ: Snowstorm spares DC, heads toward New England