Ask, how to infer whether the owner will say thank you when he finds the mobile phone?

In fact, this is a bit abstract! It all depends on the owner's personal behavior. Experienced people will say thank you, and inexperienced people will say thank you. But generally, as long as you are sincere, even if the other party doesn't say thank you, we are also good people. God knows everything, I know ~ why not?

From a moral point of view, this thorny problem is simplified at once ~