The girl sent me a photo of her, saying that time is a pig-killing knife, and knives make people old. How should I reply to her?

No matter how you reply, you can go straight to the point and say something nice, for example, years have left no trace on her face, she is still so young, and such a good photo is so beautiful. You must use it as a mobile phone screen saver, mobile phone wallpaper, which you can see every day, and so on. Sending you photos shows that you still have some good feelings for you, no matter what kind of feelings, just let you remember her and the photos she sent you. I think she sent it to you after she chose it. I hope you can keep this photo. If you are a couple, you can choose a good one and put it on the phone screen or screen saver. I'm sure she'll be happy to see it.