The pronunciation of the word grandpa is different: if you read it twice, then grandpa will become the boss of grandparents; If you read lightly, you are an uncle. If you write, don't write uncle, write uncle. For the elderly, people who are about the same age as your father or older than your father can be called uncles, or uncles, and especially big ones should be called grandfathers. In addressing, in order to make the other party less disgusted, try to address in a small room. For example, if you call him uncle when you are older, he won't be disgusted. If you are about the same age as your father, it will be even more unhappy to call him grandpa. This is also a language art. But don't be too artificial, enough is enough.