which和in，which用法的區別

which引導定語從句

This is my house， which)is small and old. 這是我的房子，它又小又舊 is studying economics， (which subject) is very important. 他正在學習經濟學， 該學科是很重要的.

in which適用於引導從句中缺失地點狀語的句子。

比如:This is the place in which heused to stay.

in which 只能用在定語從句中，等於where，在定語從句中作狀語in which可以翻譯成在……裡面

The school (that/which) he once studied in is very famous.

= The school in which he once studied is very famous.

談到which和in which用法的區別，應該指的是它們在定語從句中做關係詞，使用which還是in which，取決於將先行詞代入，從句之後，它從句中所做的句子成分，如果他在從句中作主語，賓語或表語就用which，如果在從句中作地點狀語和時間狀語，就用In which，例如，she speaks of the day in which he got the place which he worked in is famous.