I have been selling

I have been selling You should have been more patient__that customer;I'm sure that selling him the watch was possibility.A.of B.for C.with D.at 选哪个 为什么? You should have been more patient____that customer;I'm sue that selling him the watch was.You should have been more patient____that customer;I'm sue that selling him the watch was a possibility.A of B with C for D at 为什么选B呢? I have been trying I have ever been I too have been I have been to. I have been I have been in. I have been there,have been 是have been in还是have been to的缩写? i have always been there i have never been there I HAVE NEVER BEEN,能否说I never have been I have been so serious I have been so serious I-have-been-at-home I have always been you I have been loving you I have been a person . I have never been away!