I have no clue
She has no clue.
Brian:"any ideas?"
Morgyn:"I have no clue."
Brian:"She has no clue."
Morgyn:"I have no clue."
Brian:"She has no clue."
I don't have a clue.
You either don't know the answer, or you're pretending you don't.
Your girlfriend: Why is there another woman's thong under your bed?
You (looking shocked): I don't have a clue. Dog must have dragged it in from the yard.
You (looking shocked): I don't have a clue. Dog must have dragged it in from the yard.