一.instead意為“代替”“替代”,作副詞用,通常位于句尾.如位于句首時(shí)常用逗號(hào)與后面閣開.instead 在順接句子中作“代替”講,而在轉(zhuǎn)折（或逆轉(zhuǎn)）句子中作“然而”講.
例如：1.Lily isn't here. Ask Lucy instead.
Lily不在這兒,去問Lucy吧. [注意]當(dāng)instead在祈使句中時(shí),只能位于句末.
2.she didn't answer me, instead, she asked me another question.
她沒有回答我,反而問了我另外一個(gè)問題.
二.instead of是介賓短語,其意與instead相同,不同之處在于它后面常接賓語,起賓語多由名詞、代詞、介詞、短語、動(dòng)詞 + ing 形式充當(dāng).
例如：1.We'll ask Li Mei instead of Mary.
我們將去問李梅而不問瑪麗.
2.I'll go instead of her.
我會(huì)替她去.
三.instead 與instead of的轉(zhuǎn)換.
例如: 1.He didn't answer me, instead, he asked me another
question → He asked me another question instead of answering me.
2.I'll of instead of her.→She won't go.I'll go instead
參考資料：http://zhidao.baidu.com/question/5532000.html