肯定句:主语+am/is/are+动词的现在分词+其它
例句:I am playing the guitar in my room.(我正在我的房间里弹吉他)
She is drinking water.(她正在喝水)

(图片来自网络侵删)
You are cooking dinner in the kitchen.(你正在厨房做晚餐)
They are having a meeting in the classroom.(他们正在教室里开会)
My father is repairing his car.(我爸爸正在修理他的汽车)
否定句:主语+am/is/are+not+动词的现在分词+其它
例句:I'm not doing my homework.(我不是在做作业)
You are not drinking coffee. You are drinking tea.(你不是在喝咖啡,而是在喝茶)
He is not watching TV.(他没有在看电视)
We are not reading books.(我们不是正在读书)
The dog isn't running. It is sleeping.(狗狗不是在跑,它是在睡觉)