mark my words—is used to give emphasis to a warning or prophesy:
- And you mark my words, you haven’t heard the last of him.
mark you—is used to draw attention to smth. one has just said:
- He is very ambitious—like most men, mark you.
mark my words—is used to give emphasis to a warning or prophesy:
mark you—is used to draw attention to smth. one has just said: