關係代名詞

Posted by what on 2007/10/13 16:08:03

1. This is the letter which father sent from Taipei last month.

2. Is that the postcard which Grandpa sent from Hong Kong?

在第一個句子的"which"可省略, 但第二個句子卻不能省略, 能不能請大家幫忙並告訴為什麼? Thank you very much!!