He volunteered for guard duty.

他自告奋勇去站岗。

A small group of soldiers were detailed off for guard duty.

一小队士兵被派去担任警卫。

With several years of Army National Guard duty under his belt.

依仗着在陆军国家护卫队服役的几年年经验。

Like a sentinel on guard duty, or an artist working with his paints.

就像哨兵要时刻监守自己的岗位，画家要专心做画一样。

The paper deals with the safety-guard duty of real estate manager in four parts.

文章通过四个章节研究住宅小区物业管理者的安全保障义务。