Could you tell me how to call. 你能告诉我如何打电话吗？ How much is a phone call within the city? 打一个市内电话要多少钱？ Does it cost ten cents within the city? 市内要十分吗？ Which slot is for ten-cents? 哪一个是十分的投币口？
Could you change one-dollar? 你能换一块钱吗？ I put into money by mistake. 我投错钱了。
How can I return money? 我如何拿回钱来？
