the control of traffic by a policeman stationed at an intersection
例句
用作名词 (n.)
A policeman must not smoke while he is on duty. 警察当班值勤时不得抽烟。
He was asleep at his post of duty. 他在值勤的岗位上睡着了。
No one was excluded from sentry duty. 人人都得站岗放哨。
At the same time, the people formed local governments, militiamen to stand sentry duty, Women's associations to fight for women's equality and many other organizations. 同时,人民建立了地方政权,组织了民兵站岗放哨,成立了妇女会为妇女的平等权利而斗争,另外,还成立了其他许多组织。