Two detectives were trailing him...是什么意思？

Two detectives were trailing him...

两个侦探正在追踪他。

two

n. 两个，两个东西，两点钟，一对；adj. 两个的，我

例句
He has been absent from his desk for two weeks...
他已经有两个星期没有坐在办公桌前了。

Detectives

n. 侦探( detective的名词复数 )；

例句
He left a note at the scene of the crime, challenging detectives to catch him...
他在犯罪现场留了个条儿，向警探挑衅。

were

be的过去时复数和第二人称单数形式，有时代替 was,用于条件从句、动词 wish 之后等；

例句
Shops, houses, and vehicles were set ablaze.
店铺、房子和车辆全都陷于火海。

trailing

n. 泥浆彩饰；adj. 拖尾的，曳尾的，被拖动的，蔓延的；v. （使某物）被拖在后面( trail的现在分词 )，跟踪，追踪，（在比赛等中）输，（尤指跟在他人后面）疲惫地走；

例句
Two detectives were trailing him...
两个侦探正在追踪他。

him

pron. (he的宾格)他；

例句
They said goodbye to him as he got aboard the train at Union Station.
当他在联合火车站登上火车之际，他们向他道别。