作为介词短语，它主要作状语（目的状语、伴随状语或方式状语），修饰动词、句子或说明主语的状态；后面需接名词、代词或动名词（即名词性成分）。
强调行动的目的，说明“做某事是为了获得/实现某事物”。
Many people move to big cities in pursuit of better job opportunities.
很多人搬到大城市是为了追求更好的工作机会。
The artist spent his entire life in pursuit of perfection.
这位艺术家毕生都在追求完美。
She quit her high-paying job in pursuit of a more meaningful life.
她辞去了高薪工作，追求更有意义的生活。
强调行动的过程，说明“在做某事的同时，正在追寻某事物”。
The detective traveled across the country in pursuit of the missing witness.
侦探走遍全国，寻找失踪的证人。
We hiked through the forest in pursuit of the rare bird species.
我们徒步穿越森林，追寻这种稀有鸟类。
意为“紧追不舍；穷追猛打”，强调“追赶的紧迫性”。
The police car was in hot pursuit of the stolen vehicle.
警车紧追那辆被盗车辆。
The hunters were in hot pursuit of the deer when it suddenly vanished into the woods.
猎人正紧追鹿群，这时鹿突然消失在树林里。
"pursue" 是及物动词，直接接宾语（sth./sb.），表示“主动追求/追赶”：
He pursues his dream of becoming a musician.（他追求成为音乐家的梦想。）
"in pursuit of" 是介词短语，需与动词（如 be, work, go 等）搭配使用，侧重“处于追求的状态或过程中”：
He is in pursuit of his dream of becoming a musician.（他正在追求成为音乐家的梦想。）
He works hard in pursuit of his dream.（他为了追求梦想而努力工作。）
书面语中更常见（如议论文、正式文章），但日常口语也可使用，例如：
— Why did you start learning painting?（你为什么开始学画画？）
— In pursuit of creativity and joy.（为了追求创造力和快乐。）
综上，"in pursuit of sth." 是一个表达“主动追求”的常用短语，核心是通过行动向目标靠近，需结合具体语境选择搭配的动词和修饰对象。