甚麼是Relative Clauses?用中文來回答!急!

逗號(,)係用在冇定義性（non-definding )的情況
e.g. Mary , who likes collecting stamps , is my sister .

即使冇呢個”who likes collecting stamps”唔會影響意思

相反( definding )

The girl whose dress is blue is my friend.

指明出意思

Which 是有多個選擇
who是誰
whose 是誰的
when 是何時
where是那裏