易错点一：不能准确地理解“关系代词和关系副词”具有的三大功能。
①在从句开头引导一个定语从句。②指代或替代“先行词”且先行词不可省。但在某些情况下，先行词有时也可省略。③在定语从句中作某个成分。
例 1.I’ll talk about a newly-opened market ______ you can get all ______ you need.
A. in which; which B. where; that
C. where; what D. which; that
解析：此题答案为B，学生易选D。这里面特别要注意定语从句“关系词”的第三种功能即引导词要在定语从句中作某个成分。a newly-opened market在定语从句中充当地点状语，所以应排除D项。all后面如果跟关系词应该用that。
【巩固性练习】
1.We’re just trying to reach a point _______ both sides will sit down together and talk.
（2006年山东卷）
A. where B. that
C. when D. which
2. Women ________ drink
more than 2 cups of coffee a day have a greater chance of having disease than those _______ don’t. (2006年北京卷)
A. who; / B. /; who
C. who; who D. /; /
3. Look out！Don’t get too close to the house ____
___ roof is under repair. (2006年福建卷)
A. whose B. which C. of which D. that
4.You can find whatever you need at the shopping center，________ is always busy at the weekend. (2006年上海春季卷)
A. that B. where C. what D. which
5. I walked in our garden， _________ Tom and Jim
were tying a big sign onto one of the trees. (2005年辽宁卷)
A. which B. when C. where D. that
Keys: A C A D C
易错点二：不能区分定语从句和其他从句或结构。
学生很难区分定语从句与强调结构、定语从句与状语从句以及定语从句与表语从句。
例2.Last term our maths teacher set so difficult an examination problem ______ none of us worked out.
A. that B. as
C. so that D. which
解析：此题选B。A项把as引导的定语从句与“so/such...that...”类结果状语混淆了。so修饰先行词时用as引导定语从句，且as刚好能作“worked out”这一及物动词短语的宾语，故as正确；而选A则只能为“如此......以致于......”的结果状语从句，此时that不在从句中作成分，句子也就缺少了宾语，因而选that错误。
【巩固性练习】
1.I was told that there were about 50 foreign students
_______ Chinese in the school, most _______ were from Germany. (2006年辽宁卷)
A. study; of whom B. study; of them
C. studying; of them D. studying; of whom
2.If you are traveling _______ the customs are really foreign to your own, please do as the Romans do. (2006年天津卷)
A. in which B. what C. when D. where
3.There is much chance _______ Bill will recover from his injury in time for the race. (2006年天津卷)
A. that B. which C. until D. if
4.It was not until nearly a month later ________ I received the manager’s reply. (2005年全国卷Ⅰ)
A. since B. when C. as D. that
5. Great changes have taken place in that school. It is no longer ______ it was 20 years ago, _______ it was poorly equipped. (2005年湖北卷)
A. what; when B. that; which
C. what; which D. which; that
Keys: D D A D A
易错点三：不注意介词+关系代词引导定语从句时的介词的习惯搭配。
通常选择合适的介词依据如下：①介词与定语从句的先行词是一种习惯性搭配。②介词与从句中的动词是一种习惯性的搭配。③介词与从句中的形容词一起构成一种习惯性的短语。④表示“所有格”或“整体和部分关系”时用介词of。
例 3.The train ______ she is traveling is arriving.
A. by which B. in which
C. that D. which
解析：此题选B。表乘车的搭配有by train in/on the train两种，但which代替的是the train，用by which则等于用by the train，可知其中多了一个the，故该题只能选B项(in which=in the train)。
【巩固性练习】
1 .I saw a woman running towards me in the dark.
Before I could recognize who she was, she had run back in the direction _______ she had come. (2006年重庆卷)
A. of which B. by which
C. in which D. from which
2.I was given three books on cooking，the first _________