机就是那个男人，她从他的房间偷走地图。
8. “介词+ which +不定式”。此种用法多见于正文体中，相当于一个带有主语和谓语的定语从句。如： She had only 1.87 with which to buy (= she could buy) Jim, her husband, a present. 她只有一元八角七分钱，用这些钱她给丈夫吉姆买一件礼物。分句中分别可作时间、地点和原因状语，代替相应的关系副词when, where和why。如：
①I still remember the day on which (= when) I first came to school. 我仍然记得初来学校的那一天。
②The factory in which (= where) I work is a large one. 我工作的工厂是一个大厂子。
③This is the reason for which (= why )he was put in prison. 这就是他为什么被关起来的原因。 介词的正确选择
1. 根据后面动词和介词的搭配关系选择。如：
①This is not the book of which the teacher spoke in class. (speak of 意为“谈论”，相当于talk about)
②The two things of which they felt proud were Jim’s gold watch and Della’s hair. (be / feel proud of 为固定短语，意为“以??自豪”。) 2. 根据前面的名词的搭配关系选择。如：
①I’ll never forget the day on which I first met him. (表示具体的某一天，介词用on)
②The boy pointed to the direction in which he would run. （“朝??方向”，介词用in）
3. 有时需同时考虑动词和介词的搭配关系及介词和名词的搭配关系。如：
The clever boy made a hole in the wall, through which he could see what was happening inside the house. 三、介词和关系代词
1）介词后面的关系代词不能省略。
2）“that”前“Do you”作介词的宾语，且可以省略。
例如：（1）The school（that/which）he once studied in is very famous. “that/which”可以省略。= The school in which he once studied is very famous.“which”不可省略。
（2）Tomorrow I will bring here 用，如：look for, look after, take care of等。T This is the watch which/that I am looking for.（T=正确）F This is the watch for which I am looking.（F=错误）
2. 若介词放在关系代词前，关系代词指人时用“whom”，不可用“who”或者“that”；指物时用“which”，不能用“that”；关系代词是所有格时用“whose”
（1）The man with whom you talked is my friend.（T）The man famous. （2）I bought many books yesterday, three of which are written by Lu Xun. 四、关系代词关系代词（一般情况下）“that”可用在从句做主语，谓动词的宾语，但是不能做介词的宾语。“which”指物，在从句中作主语；“whom”在从句中作宾语；“why”在从句中修语，先行词通常是“the reason”；有时“why”也可用“for+which”代替。
例：A doctor who looks after people's health.主语 谓语 先行词 定语从句修饰先行词五、判断介词和关系代词方法一： 用关系代词，还是关系副词完全取决于从句中的谓语动词。不及物动词后面无宾语，就必须要求用关系副词或者是介词加关系代词；而及物动词后接宾语，则要求用关系代词。
例如： This is the mountain village where I stayed last year.
判断改错:（错） This is the mountain village where I visited last year. （错） I will never forget the days when I spent in the countryside. （对） This is the mountain village (which) I visited last year.
（对） I'll never forget the days (which) I spent in the countryside. 例. Is this the museum ____ the exhibition was held?A. where B. that C. on which D. the one,解析： 主、谓、宾俱全，从句部分为句子的状语表地点，既可用副词where，又因 in the museum词组，可用介词in + which 引导地点状语。而此题中，介词on 用的不对，所以选A。
关系词的选择依据在从句中所做的成分，先行词在从句中做主、宾语时，选择关系代词（who, whom, that, which, whose）； 先行词在从句中做状语时，应选择关系副词（“where”地点状语，“when”时间状语，“why”原因状语）。 关系词
只用that不用which
1）当先行词是或被序数词，最高级，不定代词修饰时，关系词用that不用which。 2）当先行词既有人又有物时，用that。
3）当先行词带有the only,the very,the same,the last,the one等词时，用that不用which。
4）当主句中有who或which时，为避免重复用that。
5）当先行词为something，anything，nothing，none，no，little，much，all等不定代词时用that。 只用who不用that
1）如果先行词是those,they,all,persons,people,he,anyone,one时用who不用that
2）当先行词指人并含有较长的后置定语从句或在被分割的定语从句中时。 只用which不用that
1）当主句先行词后有介词时，用which。This the one of which I'm speaking。 2）非限定性定语从句，用which。
3) 描述句中一般用which。Beijing，which was China's capital for more than 800years。
4）those +复数名词之后，多用which .Shopkeeper want to keep a number of those goods which sell best。
5）先行词本身是that时，用which，不用that。
1）当表示时间或地点的名词作先行词时，要判断出它们在从句中作状语还是主语或宾语。作状语时用关系副词，反之用关系代词。
典型例题：I can never forget the day _______ we worked together and the day ______ we spent together.
A. when; which B. which; when C. what; that D. on which; when
解析：两个先行词the day都是表示时间的名词,但第一个空白处要填的关系词在从句中作状语,因此要用关系副词when. 第二个空白处要填的关系词在从句中作动词spent的宾语,因此要用关系代词which或that来引导定语从句. 答案：A
2）当主语为物时，不能用what
3）there be句型中，指人用who指物用that。 4）当主句中缺少主语或表语时，用the one。
5）当出现先行词+介词时，关系词只能用whom或which