一、用法:1)表示过去发生或已完成的动作 对现在造成的影响或结果;2) 表示过去已经开始并一直持续到现在的动作或状态。 E.g. H e has learned English since 2001.二、构成:由“助动词have / has+ 动词的过去分词”构成的;规则动词的过去分词构成与过去式相同,不规则动词的过去分词则需逐个记忆。 三、时间状语:already, yet, ever, never;since+时间点,for+一时间四、句式1. 肯定句:主语 + have / has + 过去分词 (+ 其他)2. 否定句:主语 + have / has + not + 过去分词(+ 其他)3. 一般疑问句:have/ has + 主语 + 过去分词(+ 其他)五、不规则动词过去式、过去分词表(1) AAA型(动词 原形、过去式、过去分词同形)cost(花费) cost cost cut(割) cut cuthit(打) hit hit hurt 伤害) hurt hurtlet(让) let let put(放) put putread (读) read read (2) AAB型(动词原形与过去式同形)beat(击打) beat beaten(3) ABA型(动词原形与过去分词同形)become(变成) became become come(来) came comerun(跑) ran run(4) ABB型(过去式与过去分词同形)dig(挖) dug dug get(得到) got gothang(吊死) hanged hanged hang(悬挂) hung hunghold(抓住) held held shine(照耀) shone shonesit(坐) sat sat win (赢) won wonmeet(遇见) met met keep (保持) kept keptsleep(睡) slept slept sweep(扫) swept sweptfeel( |