题目内容：

Kate：You're late today! I have waited here for twenty minutes.

Paul：I'm really sorry.1.

Kate：Why didn't you drive your car? It's faster than taking a bus.

Paul：2.

Kate：Really？But why?

Paul：Because I think it's our duty to care for our environment.

Kate：You have changed a lot.3.

Paul：I joined a volunteer club－Green Helper.The environmental problem is becoming more and more serious.It is time to take action to protect the environment，such as taking short shower，recycling books and paper，4.

Kate：Well.They are easy and useful.But it's not convenient to go to work without driving a car.

Paul：5.

Kate：Good idea.You're living a low－carbon(低碳) life and it's also a good way to exercise.

A．What made you do that?

B．I had to wait for a bus for a long time.

C．What's wrong with your car?

D．I am going to buy a bike and then ride to work.

E．I won't drive unless it is necessary.

F．turning off the lights before leaving.