1.同位于從句與前面名詞是同位關(guān)系,即說明前面名詞的內(nèi)容
定語從句與前面名詞是修飾與被修飾關(guān)系,即限定名詞的范圍
e.g The news that I have passed the exam is
true.
The news that he told me just now is
true.
2.同位于中的that是連詞,但a.不充當(dāng)任何成分；b.沒任何意義；
c.不能省略
定語從句中的that是關(guān)系代詞,除連接作用外,還可充當(dāng)主、賓
等（作賓語時可省略）
e.g.The idea that computers can recognize
human voices surprises many people.
The idea that he gave surprises many
people
如何判斷一從句是定語從句還是同位于從句?
用系動詞be的形式去判斷,如果是"表語從句"則是同位語從句,否則為定語從句.