Grandpa wants to send a writing brush for his birthday. What should he write?

Generally speaking, if you want to keep it simple, write a pair of birthday characters and use red rice paper with a design of a peach sent by a dragon or crane. You can sprinkle gold that night, write a congratulatory message in the last paragraph, and write down the time to make birthdates more atmospheric. If you want to be more complicated, you can write that happiness is like the East China Sea, and longevity is better than Nanshan, or happiness is like flowing water in the East China Sea, and longevity is better than Nanshan. Birthday, naturally I hope he can live a long life.