21. By this time tomorrow I,,, for three hours. A) will fly B) will be flying C) will have fly D) will have been flying 22.The man looked so miserable that she burst into A) laughing B) laughter c) tears D) crying 23, Dave since he left three days ago A) didn't see B) hasn't been seen C) hasn't seen D) wasn't being seen 24. She couldn't help when she saw his haircut A) laughs B) laughing C) laughed D) to laugh 25. What... about when I entered the office? A) were you talking B) did you talk C) you talked D) had you talk 26. She TV since this morning B) has been watching A) watches D) was watching C) watched 27. He on his own A) wasn't used to living B) didn't used to living C) wasn't used to live D) wouldn't