It's important to know one's own head before making a big decision.

Before committing to the project, he had to know what one is about and how his decisions would affect the outcome.

Excuse me, do I know you from somewhere?

When she called me stubborn during our argument, I shot back, 'it takes one to know one'.

After twenty years in the kitchen, Chef Morales seems to know every trick in the book when it comes to making sauces.

She seems to not know which end is up when she's asked to make basic decisions.

He wouldn't know someone from Adam if he bumped into him on the street.

Before we decide to go through with the plan, you know what they say: better safe than sorry.

When tackling complex wiring, it's important to know what one is doing.

When her landlord raised the rent and her savings were gone, Maria did not know which way to turn.