I'm really sorry for being late again.这里的BEING为何要用ing形式啊?

I'm really sorry that I have kept you_______(wait) for me so long. Sorry I'm really injured中文 I'm really sorry for hurting you,please forgive me.乃意思? I'm so sorry!was really sorry very much i'm sorry for your I`m sorry for it really sorry for 英语 I'm really sorry!I have to leave! I'm sorry dear!I really care about you. Sorry.I don't want that...I'm really Sorry.I really need i really am sorry I really feel sorry for you,my dear I really feel sorry for you,my dear sister Sorry,I really don't feel for you it was really(),i was()sorry for them （可怕） I'm really sorry to have_____ your bike for so many days.A.borrowed.B.had.C.Lent.D.Lost I'm really sorry for being late again.这里的BEING为何要用ing形式啊?