作业精灵老师示例：
1.
Yang Ling: How do I get to your home, Su Hai？
Su Hai: You can take the metro. You can get on the metro at Park Station and get off at
City Library Station. Then, walk to Moon Street. There's a bookshop on the street. My
home is next to it.
Yang Ling: All right.
2.
Yang Ling: Excuse me, how do I get to the bookshop on Moon Street？
Policeman: Go along this street. Turn right at the traffic lights. Then, go along Moon
Street. You can see the bookshop on your right.
Yang Ling: Thank you.
