1 What (be).....is..........your sister doing now? She (skip)....is skipping..........
2 There (be)...are........a lot of people at the party last night.
3 Kate (play)......plays.........volleyball every afternoon,but she (play)........is playing.......badminton now.
4 We should (do)......do..........morning exercise
5 He (see).......saw...............a big dragon in his dream.
6 Laura ( be)....is...........from Canada.She (speak)........speaks.........English and French.
She (come)......will come............to VietNam tomorrow . She (stay)......will stay...........in a hotel in HCM City for 3 days. She (visit)......will visit.........a lot of places of interest in Vietnam
7. My brother can (swim)......swim.............
8. I prefer (live)...........live..........in a village because it is peaceful.
9. There (be)...........is...................a chair and two tables in the room.

giải thích 

   khẳng định : S + am/ is/ are + V-ing

   phủ định     : S + am/ is/ are + not + V-ing

   nghi vấn      : Am/ Is/ Are + S + V-ing  ?

   sau động từ khuyết thiếu thì giữ nguyên