助動詞have的用法和例句
have作爲(wèi)助動詞可以:
1.搆成完成時(shí)態(tài)(have+過去分詞): What has happened? 出了什麼事? He told me Jane had left. 他告訴我簡已經(jīng)走了。 She will have arrived by this time tomorrow. 明天這時(shí)她就會到了。 How long have you been there? 你在那裡待了多久?
2.搆成完成進(jìn)行時(shí)態(tài)(have+been+現(xiàn)在分詞) We have been trying to contact you. 我們一直在想和你聯(lián)系。 She has been teaching there for thirty years. 她在那裡任教達(dá)三十年。 That was the book he had been looking for. 這是他一直在找的書。
另外,have (got)to還可搆成謂語,表示“不得不”: We have(got)to be careful. 我們得小心。 You don’t have to worry. 你不必憂慮。