Mary: Hi, Steven! What do you like to do during the weekend?
Steven: I love swimming and cycling. On Saturday morning I usually ride my bike around the city or along the country road for almost two hours.
Mary: That's great! I think they do you a lot of good.
Steven: Sure, they do.
Mary: But why do you choose cycling at first?
Steven: Because it is convenient and good for environmental protection.
Mary: You are really a good citizen.
Steven: That's what I can do.

玛丽：嘿，史蒂文，你周末喜欢做什么？
史蒂文：我喜欢游泳和骑自行车，星期六早上我要花两个小时骑车在城里转一转，或沿着乡间小路骑车。
玛丽：真不错，我想锻炼对你有很多好处。
史蒂文：确实是。
玛丽：但是最初你怎么会选择骑自行车。
史蒂文：因为骑自行车既方便又环保。
玛丽：你真是个好公民。
史蒂文：这只是我能做的。