What are they 现在进行时 doing now?
do tell play doing telling playing cook pick study cooking picking studying
live write living writing ride dance riding dancing
sit hop cut sitting hopping cutting stop jog run stopping jogging running
肯定句 否定句 一般疑问句 特殊疑问句
主语+be(am/is/are ) +现在分词 +…
主语+be not +现在分词+… I am not writing a letter. =I’m not writing a letter.
They are not having a game. =They aren’t having a game.
She is not singing with her sister. = She isn’t singing with her sister.
Be+主语+现在分词+…? Are you listening to the video? Yes, I am. / No, I’m not.
Is she cleaning the room? Yes, she is. / No, she isn’t.
I am doing my homework. Are you doing your homework? What are you doing?
He is singing and dancing on the stage. Is he singing and dancing on the stage? Who is singing and dancing on the stage?