现在完成时（I ）语法知识定义：（1）表示过去发生或已经发生的动作对现在造成的影响或结果，这个影响和结果对现在还必须存在.常与already （已经）,yet（已经，还）,just （刚刚）,ever （曾经），never 等词连用.already 常用于肯定句或疑问句（均表示：已经）.yet : 常用于否定句（表示：还、尚）,疑问句末尾（表示：已经）. 现在完成时的构成及句型结构：（注：过去分词的变化分规则变化与不规则变化，规则变化与动词原形变过去式一样，不规则变化见教材137 页）1.肯定句：主语+have/has+ 过去分词+其他+时间.eg: I have already lost the key. 我已经弄丢了钥匙.（我现在没有钥匙）He has ever read that book ? 他曾经看过这本书.（了解书的内容）They have just cleaned their hands. 他们刚刚洗过手了.（手是干净的）2.否定句：主语+haven ' hasn't+ 过去分词+其他+时间.eg: I haven ' lost the key yet.He hasn'tever read that book .They haven'tjust cleaned their hands.3.—般疑问句：Have/Has+ 主语+过去分词+其他+时间？肯定回答：Yes, 主语+have/ has. 否定回答：No, 主语+haven t/hasn t. eg: Have you already lost the key? Yes, I have. No, I haven't.Has he ever read the book? Yes, he has. No, he hasnt. Have they justcleaned their hands? Yes, they have. No, they haven't.4.特殊疑问句：特殊疑问词+have/hasn 主语+过去分词+其他+时间？eg: What have you already done? （done 是do/does 的过去分词）What has he ever done?What have they just done?定义：（2）现在完成时表示从过去开始一直持续到现在还有可能继续持续下去的动作或状态。
eg: She has learned Englishor 5 years. （她已经学习五年英语了）解释：一直在学，持续了五年，并且还可能持续学下去.He has lived in Beijingsince he was born ? （自从他出生以后就居住在北京）解释：从出生后就一直住在北京，持续到现在，还有可能一直住下去）Have you stayed heresince 3 o ' clock? （自从 3 点后你就一直呆在这儿吗？）例题：选用for 和since 填空:1.W e haven' t seen each other ___ a long time.2. His father has been in the factory ___ 10 years ago.3. The film has been on 20 minutes. ____________________4. Mr. Green has worked here __________ he came to China.5. His grandparents have been dead __________________________________________ several years.6. It ' s five years _____________ we met last time7」have already had dinner. （否定） ____________ I _________ dinner .& Mum has cooked the dinner. Mum _______ ___________ the dinner.9.Susan has learned English at school. Susan _______ English at school.10.I have already had dinner. （提问）______________________________________ ?11.He has iust finished his homework. ______________________________________ ?12.Susa n has lear ned En glish at school. ____________________________ ?13.Mum has cooked the dinner. ______________________________________________ ?（3）现在完成时与一般过去时的区别：现在完成时属于现在时态的范围，不能和表示过去的时间状语连用，女口yesterday, last night, three weeks ago, in199 等.一般过去时只表示过去的动作或状态，和现在不发生关系。
一般过去时就可以和与表示—过去的时间状语连用.eg: I have already seen the film. （现在完成时，已经看了这部电影，并且知道电影的内容）I saw the film last week. （一般过去式，因为后面有表示过去的时间状语lastweel ）He has lived here since 1993.（现在完成时，后面有since 引导的时间状语从句）He lived here in 佃93. （一般过去时，1993 年住在这儿，现在没住在这儿了）例题： 1. —__ you __ （clean） the room? Yes, we _______ （do） that already.2.W hen _____ you ______ （do） it? We _ （do） it an hour ago.3.___ he ____ (see) this film yet? Yes.4. When __ he ____ (see) it? He __ it last week.5. I _____ (read) the novel twice. It ' s in6e nigen _____ (give)up smoking last year.7. She ___ (go) to Pirs, hasn ' t shY^s. How __ she ___ (go) there? She ___ (go) there by air.现在完成时 (II )语法知识1. 构成：含有 be 动词的现在完成时的谓语部分由 构成，表示：曾经去过某地⋯ (been 是 be 的过去分词，不规则变化 )2. 基本句型：(1) 肯定句：主语 +have/has+ been + to+ 地点. eg ： I have been toAustralia.They have been to Beijing.He has been to South Africa.(2) 否定句： 主语 +haven't/hasn' t + been + to+ 地点. eg: I haven 'been to Australia.They haven ' been to Beijing.eg ： Where have you been?Where have theybeen?3. 用法：用来表示之前已经发生和完成度的动作与状态，其结果却和现在有联系 动作和 结果发生在过去，但它的影响现在还在 .可以和 never, ever, once, twice, three/four ???times 等 畐 U 词连用 .have/has+ been+ to+ 地点”(3) —般疑问句：肯定回答： Yes, 主语+ have/has.eg: Have you been toAustralia?Have they been to Beijing? Has hebeen to South Africa?(4)特殊疑问句：特殊疑问词 He hasn'tbeen to South Africa.Have/Has+ 主语 + been + to+ 地否定回答：主语 +haven t hasn't. Yes, I have. No. I haven t. ' Yes, they have. No, they haven ' .t Yes, he has. No, he hasn't.+have/has+ 主语+ bee neg: They have been to Chongqing twice I have never been to Sichuan.Has she ever been to Hainan?3I .h区av别e k:nown her since the n.eg: She has been to Shanghai. （她去过上海，已经回来了）She has gone to Shanghai. （她去了上海，还没有回来）（3） . have been in 表示“在某地呆了多少时间”，常与时间段状语连用eg: I have been in Shanghai for three years . 我至U 上海已有三年了。
He has been in London for half a month . 他来伦敦已有半个月了。
eg: The film has been on for ten minutes. 电影已经开始了10 分钟了。
例题：1? —Where is your brother? —He _____ the shop. He ' II be back soon.2.— _ you ever _____ to America —Yes, I _____ New York twice.3.—David _______ Australia. —I ' m sure has already arrived.4.——Is Benny here? —No, he ___ the school library. He left five minutes ago.4.Mike and his parents _________ the south for half a year.6.Mum is not at home now. she _________ the shop.7.You can ' t find him. H__ ____ Xi' an.8.Mr. Zhang ________ this school for ten years. He knows everyone here.9.Miss. Brown _______ China three times.10.I __________ the West lake, Look, I have taken many photos of it .11.Tom _________ Jim ' s home, but he hasn ' t come back.12.We __________ the bookshop and bought many books.13.My parents ________ Shandong for ten years.现在完成时(III ) 语法知识动词按其动作发生的方式，发生过程的长短可分为延续性动词与非延续性动词。