Preposiciones into y onto

Into es la unión de dos preposiciones:
The teacher is in the room.
The teacher is going to the room.
The teacher is going into the room.

Into = hacia dentro de, en la dirección de (entrada)
We are going into town.
The car came into the parking lot.
The meeting lasted into the night.
The book was translated into German.

Onto es la unión de on y to:


He is walking to the horse.
He is on the horse.
He got onto the horse.

Onto = to a place, position on, upon.

Mary held onto her umbrella.
The climbed onto the roof.
He jumped onto his bed.