我是1999年的古董菇凉
[wŏ shì 1999 nián de gŭ dŏng gū liáng]
I am an antique girl born in 1999. Here, describing oneself as 'antique' humorously refers to older technologies, trends, or memories associated with the year 1999; it shows self-mockery about no longer being fashion-forward or young, expressing a humorous self-description.