Sorry I'm late.How long has the meeting been on?

Sorry,I'm late.How you been here long No.I ___half an hour a how long has the meeting()? How long has the hous been on fire The meeting has been on,but I don't know where the meeting _ How long has the shop been open The meeting ___when I got there.A has begun B has been on C 英语现在完成时 How long has the film been on?为什么要用on? -How long has the film been on?-___3:30.A.At B.About C.Befor How long has the movie been on It ___ five minutes _____. Sorry,I'm late.-----( I'm sorry ( ) late The meeting has been on since an hour ago