I am sorry ,I am late,did you have been waiting for a long t

I am sorry you have been waiting so long .BUT I am sorry to have kept you waiting for a long time. I am t__ sorry I have kept you waiting long. I am sorry you have been waiting so long .but it will still I am very sorry for keeping you waiting so long. I am sorry for keeping you waiting for a long time为什么用keepin I am sorry to keep you waiting for me for a long time I am t() sorry I have let you wait long I am waiting for you.和I have been waiting for you.的区别 I am sorry I _____(keep)you waiting so long. --i am sorry to have kept you waiting long ---never mind .i i am sorry to keep you waiting so long