.---I'm sorry, but there's no smoking room in this section on the train.

　 ---Oh, I _____ that, and I won't smoke again.

—I'm sorry, but there's no smoking room in this section on the train．

—Oh, I ____that, and I won't smoke again．

       A．don't know   B．won't know          C．didn't know   D．haven't known

 —— I’m sorry, but there’s no smoking room in this section on the train．

—— Oh, I ___________that, and I won’t smoke again．

       A．don’t know                                       B．won’t know       

       C．didn’t know                                    D．haven’t known

---I’m sorry, but there’s no smoking room in this section on the train.

---Oh, I _____ that, and I won’t smoke again.
　

1. A.
   don’t know
2. B.
   won’t know
3. C.
   didn’t know 　　
4. D.
   haven’t known