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' 。
Kidnappers are rarely interested in animals, but they recently took considerable interest in Mrs.Eleanor Ramsay's cat.
绑架者很少对动物感兴趣。最近,绑架者却盯上了埃莉诺。拉姆齐太太的猫。