1．作介詞，表示“作為； 當作”。如： As a party member, I must be strict with myself． He works in the school as a teacher of math． 2．作連詞，引導方式狀語從句，意為“像；按照”。 如： You must do everything as I asked you to． 3．作連詞，引導時間狀語從句。意為“當……的時候”。 如： She sings as she walks． He came just as I reached the door． 4．作連詞，引導原因狀語從句。如： You must hurry up as there is little time left． 5．引導讓步狀語從句，常用於倒裝結構 。如： Hard as he worked, he didn’t pass this examination． Child as he is, he knows a lot． 6．用作關系代詞，引導非限制性定語從句。如： As we all know, the earth is round． She has been late again, as was expected． 7．用於壹些固定搭配。如： ① as ．．． as．．． 與……相同的程度； 與……等同 The dress is twice as expensive as that． ② as if ／as though 似乎；好像 He behaved as if nothing had happened． He rubbed his eyes and yawned as though waking up after a long sleep． ③ as well as 同（壹樣也）；和；還 On Sunday? his landlady provided dinner as well as breakfast． We cannot expect her to do the homework as well as look after the children． ④ such．．．as 像……這樣的；such as 例如 I bought a lot of fruits, such as apples, oranges, bananas and so on． Such simple actions as eating? drinking become difficult． ⑤ as for 至於某人（某事物） As for you, you ought to be ashamed of yourself． As for the hotel, it was very uncomfortable and miles away from the sea． ⑥ as to 關於某事物；提到某事物 As to correcting our homework, the teacher always makes us do it ourselves． ⑦ so as to ．．． 以便, 為了 She saved the money so as to support the family． ⑧ as a matter of fact 其實；實際上 As a matter of fact, I’m very fond of housework． ⑨ as a result 結果 (發生某種情況) As a result， he had been given an excellent job． ⑩ as long as 只要 As long as you work hard, you will succeed sooner or later．