For people in different age groups relative to you, there are slightly different ways to talk about age:

1. Adult around your age

If you are talking to an adult, from late teens to an age that is not too much older than you, you can ask for the person’s age by saying 你今年多大(nǐ jīnnián duō dà)?

2. Child younger than ten years old

If you were talking to a child, probably less than 10 years old, the question you would ask instead will be 你几岁了(nǐ jǐ suì le)?

3. Elderly person

The final kind of situation is when you are asking a more elderly person their age. In this kind of situation, you would say 您多大年纪了(nín duō dà niánjǐ le), employing the honorific form of “you”, 您(nín)?

We can see that the change aspect particle 了(le) can be added to the end of all these questions, as well as the answers involving age. This adds to the emphasis that age is something that is constantly changing, and so the age you have become now is a new state.

了(le) can also add certain emotions and feelings to the sentences depending on the situation and context. A child could reply 我今年五岁了(wǒ jīnnián wǔ suì le), or “I’m already five years old,” with 了(le) conveying a sense of pride. On the other hand, an elderly person could reply 我七十二了(wǒ qīshí’èr le), or “I’m already seventy-two,” with 了(le) conveying a sense of achievement or lament depending on the intonation.