一.概念：表达现在正在做某事。(标志词：now 现在, look 看, listen 听, at present 目前at the moment 此刻，right now 立刻二基本结构：a.肯定句: 主语+be（即am is are） +v-ing+其它. 如: I am reading a book.b.否定句：直接在be后加not. 如：I am writing. I am not writing.c.一般疑问句及回答:问句,直接把be提前,肯定回答:Yes,主语 +be 否定回答: No,主语+be+not -Are you drawing ?-Yes,I am./No, Im not三、规则动词变化规律：一般情况下，动词后直接加ingworking, buying, visiting, talking, saying以不发音e结尾动词，去掉e，然后加ingtaking, having, using, driving, writing, practicing以辅音字
