用法不同。as well往往用在句尾，表示“還，也”的意思。as well as常用來連接兩個并列的成分，作“也，還”，它強調的是前一項，后一項只是順便提及，因此連接并列主語時，謂語動詞與前一項一致。

as well as用于本義，可視為as…as結構與well的自然搭配，其意為“與……一樣好”，在否定句中可用not so well as代替not as well as。如：

He speaks English as well as her.他說英語說得跟她一樣好。

用于引申義，表示“不但……而且”“既是……也是”“而且”“還”。如：

He grows flowers as well as vegetables.他既種菜也種花。

有時還可譯為“除……之外，還”，與besides， in addition to的用法相似。如：

As well as learning to swim he has been taking Spanish lessons this summer.今年夏天，他除了學習游泳外，他還在上西班牙語課。

當as well as連接兩個成分作主語時，其后的謂語通常要與前面一個主語保持一致。如：

Tom as well as his parents is going toLondon.湯姆和他的父母要去倫敦。

as well as通常被視為介詞，所以后接動詞時，一般用動名詞形式。如：

He sings as well as playing the piano.他不但會彈鋼琴，而且會唱歌。

as well as后接動詞用動名詞的情況主要見于主句謂語為簡單時態(tài)(即一般現在時和一般過去時)的時候。

如果主句謂語為復合時態(tài)(即其中含有情態(tài)動詞或助動詞)，則as well as后的動詞通常要與情態(tài)動詞或助動詞后的動詞形式保持一致。如：

Students should pursue their own interests， as well as do their school work.學生不僅應該做要好家庭作業(yè)，而且還要有自己的興趣。

如果as well as是連接兩個不定式，則其后用不帶to的不定式。如：

A museum should aim to entertain as well as educate.博物館不僅要有教育性還且還要有娛樂性。

當as well as用于句首時，其后習慣上要接動名詞。如：

As well as eating a seven-course meal， they drank three bottles of wine.除吃了一頓有七道菜的飯之外，他們還喝了三瓶酒。

as well as有時也被視為準并列連詞，后接的動詞可以與主句謂語動詞形式一致（但這種情形遠不如用后接動名詞普遍）。如：

He publishes as well as prints his own books.他不但印刷而且還出版自己的書。

來源：高三網