约3640字。
　　《laughter is good for you-grammar and usage》教案
　　Step 1: General introduction
　　This section helps us overview present tenses. You are expected to review the four types of present tense. They are the simple present, the present continuous, the present perfect and the present perfect continuous.
　　Step 2: Explanation
　　I The present tense
　　1 表示客观事实或普通真理.(不受时态限制)
　　The geography teacher told us the earth moves around the sun.地理老师告诉我们地球绕着太阳转。
　　Japan lies to the east of China. 日本位于中国的东方。
　　The sun rises in the east and sets in the west. 太阳东升西落。
　　2 表示现在经常或反复发生的动作或存在的状态,常和often, always, usually, sometimes, everyday, once a week 等表示频率的时间状语连用.
　　He takes a walk after supper every day. 他每天晚饭后散步。
　　My mother works at the same pany as my father. 我母亲和父亲在同一家公司工作。
　　We always care for each other and help each other. 我们总是相互关心相互帮助。
　　3 表示主语的特征、性格、能力等。
　　Mr. Smith hates fish and never eats any. 斯密斯先生讨厌鱼而且从来不吃。
　　Mary speaks both English and French very well. 玛丽英语和法语都说的很好。
　　4 表示安排或计划好的肯定会出现的动作或状态。
　　The plane takes off at 10:00 a.m. 飞机上午10点起飞。
　　Tomorrow is Wednesday. 明天是星期三。
　　5 在时间、条件状语从句中用一般现在时表示将来的动作。
　　We will have to put off the sports meeting if it rains tomorrow. 如果明天下雨我们将不得不推迟会议。
　　I can’t leave unless my boss agrees. 除非老板同意，否则我不能走。
　　When you see her, just tell her that I am all right. 你见到她告诉她我很好。
　　Notes: if 引导的条件状语从句中可以用shall 或will 表示意愿，但不表示时态。
　　If you will acy invitation and e to our party, my family will be pleased.
　　如果你能接受我的邀请来参加我我们的聚会，我的家人会很高兴的。
　　II. Present continuous tense
　　1 表示说话时正在进行的动作。
　　—what are you doing?
　　—I am writing a letter.
　　It’s raining heavily now, so we must stay inside.
　　2 表示现阶段一直在进行的动作。
　　Jane is studying law while her sister is doing physics. 简在学习法律而她的姐姐在学习物理。
　　He is teaching English and learning Chinese. 他正在一边教英语一边学中文。
　　3 表示按计划近期内即将发生的动作。
　　I am meeting Mr. Wang tonight. 我今晚要去见王先生。
　　I am going to Qingdao for the summer holiday this year. 我计划今年去青岛过暑假。
　　The plane is leaving for London soon. 飞机即将飞往伦敦。
　　4 与always often 等频度副词连用表示经常反复