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 there.

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________________.