If you don't know a person's last name, use 'ma'am' or 'sir'.
如果你不知道一人的姓, 你应称呼他为 'ma'am' 或 'sir' 。
The next car the boy stopped did not take him into the centre of Paris as he hoped it would, but to Perpignan on the French-Spanish border.
男孩截住的下一辆车,没有像他希望的那样把他带到巴黎市中心,而是把他带到了法国和西班牙边界上的佩皮尼昂。