延續(xù)動(dòng)詞與瞬間動(dòng)詞

1) 用于完成時(shí)的區(qū)別 延續(xù)動(dòng)詞表示經(jīng)驗(yàn)、經(jīng)歷； 瞬間動(dòng)詞表示行為的結(jié) 果，不能與表示段的時(shí)間狀語連用。 He has completed the work.　　他已完成了那項(xiàng)工作。 (表結(jié)果) I've known him since then.　　我從那時(shí)起就認(rèn)識(shí)他了。(表經(jīng)歷)

2)用于till / until從句的差異 延續(xù)動(dòng)詞用于肯定句，表示"做……直到……" 瞬間動(dòng)詞用于否定句，表示"到……，才……" He didn't come back until ten o'clock. 他到10 點(diǎn)才回來。 He slept until ten o'clock.　　　　　 他一直睡到10點(diǎn)。

典型例題 1. You don't need to describe her. I ___ her several times.　 A. had met　B. have met　 C. met　D. meet 答案B. 首先本題后句強(qiáng)調(diào)對(duì)現(xiàn)在的影響，我知道她的模樣，你不用描述。再次，several times告知為反復(fù)發(fā)生的動(dòng)作，因此用現(xiàn)在完成時(shí)。

2.---I'm sorry to keep you waiting. ---Oh, not at all. I ___ here only a few minutes. A. have been　 B. had been　 C. was　D. will be 答案A. 等待的動(dòng)作由過去開始，持續(xù)到現(xiàn)在，應(yīng)用現(xiàn)在完成時(shí)。