阅读下面的对话，根据上下文，从方框内选择恰当的选项补全对话，使句意完整、符合（其中有两项为多余选项）
Crum，is talking with his doctor．A is for Mr．Crum，；B is for the doctor．
B：Mr．Crum，please．
A：Hello，doctor．
B：How are you？
A：I'm Fine，thank you，doctor，but I need your advice．I want to give up smoking．
B：That's a good idea．Smoking is very bad for your health．（71） ______
A：I started smoking when I was 22．That's 25 years ago．
B：（72） ______
A：Yes，I've tried several times，but I always start smoking again．Now，my daughter has asked me to give it up，and I want to try again．（73） ______ And I want to succeed this time．
B：Well，let's see．I'll listen to your breathing，and do some tests．Have you got a cough？
A：（74） ______ And I'm not fit．I get a lot of colds．
B：Well，it's really a good idea to stop smoking．Smoking causes many illnesses，not only cancer．
A：（75） ______ B：One thing you can do is to join a group．That often works，because you have other people to help you．

A．Yes，I have． B．When did you start smoking？ C．No，I haven't． D．She's afraid I'll get cancer（癌症）． E．What other illness does smoking cause？ F．And have you tried to give up？ G．How can I give it up？