let alone
leave alone
Let alone : Even less; certainly not. Used after a negative clause.
I can't add two and two, let alone do fractions.
Jim can't drive a car, let alone a truck.
I’m too sick today to walk to the kitchen, let alone to go to the zoo with you.
He doesn’t even speak his own language well, let alone French.
To stay away from; keep hands off; avoid; not to disturb.
When Joel gets mad, just let him alone.
Little Patsy was warned to leave the birthday cake alone.
Leave the baby alone for a while and she may go to sleep.
After the cat had scratched Peter twice, he let it alone.