You can’t unscramble a scrambled egg.
Your guess is as good as mine
You can lead a horse to water but you can’t make it drink.
You can’t fit a round peg in a square hole.
You show me the man and I’ll show you the rule.
Your name is mud
You can’t teach an old dog new tricks.
You can catch more flies with honey than with vinegar.
You can’t win them all.
You can say that again
