Usage patterns
〈人〉を置き去りにするto leave a person behind
He left his companions behind and fled.
〈物〉を置き去りにするto leave an object behind (e.g. a car, luggage)
Because of the flood, we had no choice but to leave the car behind.
〈人〉に置き去りにされるto be abandoned/left behind by someone
She was left behind in the forest.