when，where，why作为定语从句的引导词，总称为关系副词。下面用句子合并的方法分析它们的使用。

一、where引导的定语从句

分析下面两个简单句：

句①I know a garden.

句②You can find wild strawberries there.

把句②变为句①的定语从句，句①中的agarden做定语从句的先行词。在句②中there指句①中提到的agarden也就是定语从句的先行词，there在句中做地点状语，因此要用where引导定语从句，代替句②中的there，也就是说there就不能出现在定语从句中了。

由此得到

③I know a garden where you can find wild strawberries.

句②还可以写作

④You can find wild strawberries in it.

it指句①中的garden，“在花园中”要使用介词短语in the garden。）

把句④变为句①的定语从句，因为it做介词in的宾语，先行词是agarden，指物。在这种定语从句中介词常常提到定语从句的开始，这时关系代词只能使用which替代it，it就不能在定语从句中出现了。

由此得到

⑤I know a garden in which you can find wild strawberries.

请把下面每组的两句话合并为一句，把第二句话变为第一句的定语从句。

第一组：

This is the village.

I was born there.

→This is the village where I was born.

第二组：

The lab is not far from here.

The chemist often does experiments there.

→The lab where the chemist often does experiments is not far from here.

二、when引导的定语从句

分析下面两个简单句：

句①We shall remember the days.

句②We studied together then.

把句②变为句①的定语从句，句①中的the days做定语从句的先行词。在句②中then指句①中提到的the days，也就是定语从句的先行词，then在句中做时间状语，因此要用when引导定语从句，代替句②中的then，也就是说then就不能出现在定语从句中了。

由此得到

③We shall remember the days when we studied together.

句②还可以写作句

④We studied together during the days

.介词短语during the days含义为“在这些日子里”)

把句④变为句①的定语从句，因为the days做介词during的宾语，先行词是the days，指物，在定语从句中介词during提前，用关系代词which替代the days，the days就不能在定语从句中出现了。

由此得到

⑤We shall remember the days during which we studies together.

请把下面每组的两句话合并为一句，把第二句话变为第一句的定语从句。

第一组：

I've always longed for the days.

I should be able to be independent then.

→I've always longed for the days when I should be able to be independent.

第二组：

There are moments.

I forget all about it then.

→There are moments when I forget all about it.

三、why引导的定语从句

分析下面两个简单句：

句①He wanted to know the reason.

句②I was late for the reason.

把句②变为句①的定语从句，句①中的the reasons做定语从句的先行词。因为the reason做介词for的宾语，先行词是the reason指物，在定语从句中介词for提前，用关系代词which替代the reason，the reason就不能在定语从句中出现了。

由此得到

③He wanted to know the reason for which I was late.

注意：在定语从句中当先行词为the reason(s)，定语从句由for which引导时，可以用why代替for which。

由此我们得到

⑤He wanted to know the reason why I was late.

请把下面两句话合并为一句，把第二句话变为第一句的定语从句。

The reason is not very convincing1.

He came for the reason.

→The reason why he came is not very convincing.

The reason for which he came is not very convincing.