to quickly become good friends with someone
zaprzyjaźnić się
Look at them. They really hit it off. Spójrz na nich. Przypadli sobie do gustu.
I’m really glad you two really hit it off.
It' s too bad John couldn' t make it. I know you would hit it off.
When Tim met Jim, they hit it off immediately. Kiedy Tim poznał Jima, od razu się zaprzyjaźnili.
to hit it off with sb