A: I haven’t seen Jim for a long time. Do you know where he recently is?

B: You do not know? He was in hospital.

A: hospital? What happen to him？ 

B: He fell down the stairs, his leg was injured.

A: My God, how was it?

B: He was  fighting  with several classmates on the stairs ，he  accidentally fell down. His leg was broken.

A: God, it seems we must be careful，Don’t  fight （打闹）on the stairs.