紧缩定语从句就是指把一个定语从句紧缩成“ 介词+关系代词+不定式”结构。这类结构主要用于正式文体中。

　　She must have time in which she can grow calm.=She must have time in which to grow calm.

　　她必须有冷静下来时的时间。

　　Allow me one minute in which I can change my clothes. =Allow me one minute in which to change my clothes.

　　给我一点时间换衣服

　　He was miserable unless he had neighbors with whom he could quarrel.=He was miserable unless he had neighbors with whom to quarrel.

　　他要是没有邻居吵架就难受。

　　若语义清楚，且结构恰当，“介词+关系代词+不定式”结构有时可进一步将其中的关系代词省略，而只保留介词和不定式

　　She must have time to grow calm .

　　她必须有冷静下来时的时间。

　　Allow me one minute to change my clothes .

　　给我一点时间换衣服。

　　He was miserable unless he had neighbors to quarrel with.

　　他要是没有邻居吵架就难受。