to treat her, to treat it
Sé cómo tratarla.
I know how to treat her.
— Buenos Muchachos (1990)
No debería tratarla así.
I shouldn’t treat her that way.
No deberías tratarla así.
You shouldn't treat her that way.
Hay que saber tratarla un poco.
You have to know how to handle it a little.
— Los 400 golpes (1959)