例如：polite-politely, wide-widely等。
形容詞變副詞通常是加ly,其變化有規律可循,請記住以下口訣：
一般直接加，“元e”去e加，“輔y”改i加，“le”結尾e改y。
分別舉例如下：
quick—quickly,
true—truly,
happy—happily,
possible—possibly.
另外：
一、在形容詞詞尾直接加-ly。如:real-really; helpful-helpfully; careful-carefully; hopeful-hopefully; slow-slowly; quick-quickly; quiet-quietly
二、以輔音字母加y結尾的形容詞要變y為i,然后再加-ly。如:busy-busily; angry-angrily; easy-easily
三、某些以輔音字母加不發音的字母e結尾和以-ue結尾的形容詞要先去掉e,然后再加-y或-ly。如: terrible-terribly; true-truly; gentle-gently
另外,副詞還可以由形容詞加前綴a-得來,如:loud (adj.)-aloud (adv.)
此外,部分名詞加后綴也可變成副詞,如:part-partly。
例句: It is partly her fault. 有部分是她的錯。
需注意: friendly; motherly; lovely等詞是形容詞而非副詞。
再看轉化副詞。在英語中,有些詞既可以作形容詞,又可以作副詞,如early, much, fast, little, wide, loud等。 由于這類詞詞性雖不同,但詞形卻一樣,這就需要大家學會在特定語境中判斷它們各自的詞性。例句:Thank you very much. (adv.) 多謝。There is much water in the river. (adj.) 河里有很多水。The music is too loud. Please turn it down. (adj.) 音樂聲太大,請調低點。He speaks loud enough. So everyone in the room can hear what he said. (adv.) 他說話的聲音很大,所以房間里每個人都能聽到他的話。
另外,還有一類副詞和形容詞詞義相同,但拼寫卻不同,如well和good。例句He speaks good English. 他講一口流利的英語。He speaks English well. 他英語講得不錯。
多音節y結尾的詞 將y改為i后加ly easy-easily
happy-happily
heavy-heavily
單音節y結尾的詞 直接加ly gay-gayly (gaily)
sly-slyly (slily)
以ve結尾的詞 去e加ly true-truly
以le結尾的詞 去e加y gentle-gently
possible-possibly
其他以e結尾的詞 一律加ly nice-nicely
wise-wisely
polite-politely
以ll結尾的詞 只加y full-fully
以ic結尾的詞 加ally automatic-automatically
energetic-energetically
其他形容詞 均加ly careful-carefully
glad-gladly