Tại sao lại dùng là "is to be married" mà không phải là "is going to marry"?
"To be married" is the state of being married. He uses this expression because it implies a sense of urgency or that it is happening soon since after today, his daughter will be married. This expression is also a bit more formal and old-fashioned. Ex: They are to be married today. "Going to marry" could also be used here, but it implies that the marriage ceremony is happening farther in the future. It is also less formal. Ex: She is going to marry him. The most common expression to use here would probably be "to get married." This expression is a present tense particle but can also be used to indicate that it will occur in the future. Ex: We are getting married today. Ex: I'm getting married next week.