Ответ:
— Has the post come?
— Yes, it has.
-How long have you known Mr Pinky? — I`ve known him for ten years.
-Have you ever left a restaurant without paying the bill? — No, I haven`t.
-Why haven`t you done your home task? — I haven`t had time.
I have often seen her but I have never spoken to her. (или, как вариант: I often see her but I have never spoken to her.)