提示：Lucy要去艺术展览中心，向一位男士问路，该男士告诉她如何前往。（L = Lucy; S =Sir）L: Excuse me, sir. _____ （51）the Art Exhibition Centre?S: Yes, but it is quite far. It's about an hour's walk. You can take a bus the~L:_____（52）S: You can take Bus No. 15.L:_____（53）？S: About 20 minutes. And you can also take a taxi.L: Taxi? That's a good idea. Thank you very much.S:_____（54）L: Goodbye.S:_____（55）_____. 54填_______