现在实行时（一）现在实行时表示现在（说话瞬间）或现阶段正在实行或发生的动作，常与now, these days等时间状语连用。 现在实行时由“助动词am / is / are + 动词-ing形式”构成。动词-ing形式的构成是有规律的：1. 一般情况下，在动词原形末尾直接加-ing。如：sing singing clean cleaning2. 以不发音字母e结尾的动词，去掉e，再加-ing。如：make making write writing3. 以重读闭音节结尾的动词且末尾只有一个辅音字母，双写这个辅音字母，再加-ing。如：swim swimming run running 1. 现在实行时的肯定式为“主语 + am / is / are + 动词-ing形式 (+ 其他).”。 如：I am doing the dishes now. Mike is writing a book these days.Her parents are watching TV now.2. 现在实行时的否定式为“主语+ am / is / are + not + 动词-ing形式 (+ 其他).”。如：Im not doing the dishes now. Mike is not / isnt writing a book these days.Her parents are not / arent watching TV now.3. 现在进行时的疑问式为“Am / Is / Are + 主语 + 动词-ing形式 (+其他)?”。简略肯定回答为“Yes, 主语 (人称代词) + am / is / are.”；简略否定回答为“No, 主语 (人称代词) + am / is / are + not.”。如：Are you doing the dishes now?Yes, I am. / No, Im not. 【运用】. 写出下列动词的ing形式。1. cross _ 2. take _ 3. get _ . 根据汉语意思完成英语句子或对话，每空一词（含缩略形式）。1. 我弟弟现在不在玩游戏，他正在做作业。My brother _ _ games and he _ _ his homework now. 2. 艾丽斯正在跳舞吗？是的，她正在跳舞。_ Alice _?Yes, _ _. 1. crossing 2. taking 3. getting . 1. isnt playing; is doing 2. Is; dancing; she is