你吃饭了吗？是华人文化中问候他人的经典用法，但面对外囯人包括西方人绝不可这样问候。你吃饭了吗？＝你好吗？英文说：How are you? How are you doing?
Have you had your meal？
hello， how are you?
haveyouhaddinner?didyoueatyet?haveyoueatenyourdinner?
