Constant 是“经常的、不变的”，guest 是“客人”，而welcome是“欢迎”。A constant guest is never welcome的字面意思是“一个经常来往的客人从不受欢迎”。这个短语与其字面的意思又是否一致呢？请看对话：

    A: Mary has been living with my family for a while.

    B: Oh, have you guys gotten used to it?

    A: Umm, we try to get along with her, but we also have some unhappy moments.

    B: Why?

    A: Maybe because of the differences in our habits.

    B: You’d better talk about it. Personally, I don’t like to live with other people. You know, a constant guest is never welcome.

    Note: “A constant guest is never welcome” means people don’t like those who can’t keep distance with them.