which引導的定語從句

1、A shop should keep a stock of those goods which sell best.

商店應存有最暢銷的貨物。

2、This is the family which is planning to move to the city

這是要搬進城裡的一家。

3、This is a reason which we must not forget.

這是我們不能忘記的一個原因。

4、When deep in thought, which he often was, he would forget all around him.

他常常陷入沉思，這時他就會忘掉周圍的一切。

5、He bought a book, which was written by LuXun, and which he decided to give to his friend.

他買了本魯迅寫的書，他決定送給朋友。