當(dāng)先行詞在從句中是作主語、賓語的時(shí)候,應(yīng)該用關(guān)系代詞.
反之,如果是作狀語,那么就用關(guān)系副詞
比如：
She works in the factory which lies in the north of the city.
這里的factory在后面的從句中是作主語的,所以用which引導(dǎo)從句.
She works in the factory where his father worked .這里的factory作從句的地點(diǎn)狀語,所以用關(guān)系副詞.
但是,關(guān)系副詞還可以用介詞+關(guān)系代詞來代替,這個(gè)你知道吧?