定句:主语+have/has+过去分词 否定句:主语 +have/has not + 过去分词 疑问句:Have/Has+主语+过去分词 7. 现在完成时 (1) 现在完成时的句型结构 ① 肯定句:主语+ have/has+过去分词 ② 否定句:主语 + have/has+ not+过去分词 ③ 疑问句: Have/Has +主语 +过去分词 (2) 现在完成时的用法 ① 表示到目前为止曾经有过的或未曾有过的经历和体验。 用。 如: I ' ve never beeton Africa. Have you ever been to Tokyo ? I ' ve been there three times. ② . 表示某动作从过去开始, 现在刚刚完成, 对现在有一定的影响。 常与 just, already, yet, so far 等词语连用。 如: He has just finished his new book. 注意: just now 用于过去时。 ③ .表示某动作从过去开始, 一直持续到现在,可能还会持续下去。 通常与for或since连用。 如: I have lived in Qingdao for 6 years. /since 6 years ago/since 2003/ since I came to this city. It is/has bee n …+ since 常和 never, ever, several times 等连 It 's been seven years since we last saw each other. It 's six years since he was a teacher. 注意:for+ —段时间,since后接一个过去的时间点或一般过去时的句子。 间状语和条件状语从句中代替将来完成时。 如: You can go home when you have finished your work. 比较: You can go home when you finish your work. (3) 过去分词的构成 ① 一般情况下在动词词尾后直接加 -ed。 如: listen-listened, talk-talked ② 以不发音的字母 e 结尾的动词,直接加 -d。 1/2 如: live-lived, hope-hoped ④ 在表将来的时 ③ 以辅音字母加y接尾的动词,y变i,再加-ed. 如: worry-worried, hurry-hurried ④ 以重读闭音节结尾,且结尾只有一个辅音字母的动词,双写辅音字母,再加 如: drop-dropped, plan-planned, stop-stopped ⑤ 不规则变化 如: cut-cut-cut, come-came-come begin-began-begun, lend-lent-lent -ed。 本文来源:https://www.wddqw.com/doc/806cdffc4a2fb4daa58da0116c175f0e7dd11944.html