1．Tom and his father ________ (swim) now.
2．Look !They ________ (run) along the street.
3．We ________ (practice) hard these days because we will have a big match next month.
4．What ________ he ________ (do) at nine o'clock last night.
5．They ________ (listen) to the music at that time.
6．When the headmaster came in, the students ________ (read) the text.
7．We ________ (watch) TV when suddenly the telephone rang.
8．She ________ (make) the paper flowers the whole night.
9．________ you ________ (study) English? Yes, I am.
1．Look ! He is dancing.（一般疑问句）
2．The farmers weren't working last year.（肯定句）
3．The teachers are having a meeting.（对划线部分提问）
4．The boys are cleaning their room.（对划线部分提问）
5．The singer is singing some famous songs.（否定句）
6．I am studying English, too.（变为否定句）
1．Is he dancing?
2．The farmers were working last year．
3．What are the teachers doing?
4．What are the boys doing?
5．The singer isn't singing any famous songs．
6．I'm not studying English, either．
1．I am writing a letter to my friend in Beijing．
2．What were you doing at that time?
3．I was watching TV when you called me last night．