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"Dejar" is a transitive verb which is often translated as "to leave", and "quedar" is an intransitive verb which is often translated as "to be left". Learn more about the difference between "dejar" and "quedar" below.
dejar(
deh
-
hahr
)A transitive verb is a verb that requires a direct object (e.g., I bought a book.).
1. (to put)
a. to leave 
Dejé la llave en tu buzón, como me pediste que hiciera.I left the key in your mailbox, as you asked me to do.
Deja el libro en la mesa cuando acabes de leerlo.Leave the book on the table when you are finished reading it.
2. (to forget)
a. to leave 
Dejaste el celular en mi casa. ¿No te habías dado cuenta?You left your cell phone at my place. Haven't you noticed?
3. (to abandon)
a. to leave 
Su tío no tenía hijos y, cuando murió, le dejó todo a ella.Her uncle didn't have any children, and when he died, he left everything to her.
a. to leave 
Marga anda muy despistada últimamente. Hoy dejó el grifo del lavabo abierto.Marga has been very distracted lately. She left the sink tap running today.
6. (transport)
a. to drop 
¿Quieres que te lleve hasta la puerta? - No, hay mucho tráfico y no hace falta, me puedes dejar aquí mismo.Do you want me to take you to the door? - No, there's a lot of traffic, and it's not necessary. You can drop me right here.
7. (to allow)
a. to let 
Déjame terminar esta tarea y nos vamos.Let me finish this homework and we can go.
¿Vas a dejar que acabe de hablar?Would you let me finish talking?
dejarse
A reflexive verb is a verb that indicates that the subject performs an action on itself (e.g., Miguel se lava.). 
b. to allow oneself 
No puedo creer que se dejara engañar así.I can't believe that he allowed himself to be tricked like that.
a. to let oneself go 
Es fácil dejarse cuando se está deprimido.It is easy to let yourself go when you're depressed.
A pronominal verb always uses a reflexive pronoun. (e.g., Te ves cansado.).
11. (to forget)
a. to leave 
Me dejé las llaves del carro en casa. Tengo que volver.I left my car keys at home. I have to go back.
a. to grow 
Ayer vi a Ismael. Al principio no lo reconocí. Se ha dejado barba.I saw Ismael yesterday. I didn't recognize him at first. He's grown a beard.
quedar(
keh
-
dahr
)An intransitive verb is one that does not require a direct object (e.g., The man sneezed.).
c. to be left over 
Quedó bastante pollo para alimentar a los perros.There was enough chicken left over to feed to the dogs.
d. to have left 
No nos quedan huevos. Hay que comprar más.We don't have any eggs left. We need to buy more.
c. to arrange to meet 
He quedado con mi abogado a las 10 am porque quiero pedirle consejo sobre el tema.I've arranged to meet my lawyer at 10 am because I want to ask him for advice on the matter.
4. (to look)
5. (to wait)
a. to stay 
No me pidas que quede si no vas a volver.Don't ask me to stay if you are not coming back.
6. (to end up)
a. to come in 
Me dio una punzada y quedé última en la carrera de natación.I got a stitch and came in last in the swimming race.
b. to finish 
Quedamos terceros. Por lo menos nos llevamos una medalla.We finished third. At least we got a medal.
8. (to appear)
a. to look 
Si no queremos quedar como idiotas, es mejor que lo pensemos bien.If we don't want to look stupid, we'd better think about it carefully.
quedarse
A pronominal verb always uses a reflexive pronoun. (e.g., Te ves cansado.).
a. to stay 
Nuestros primos se quedaron con nosotros durante la Navidad.Our cousins stayed with us over Christmas.
10. (to retain)
11. (to recall)
a. to remember 
No se me queda la lección después de haberla aprendido.I can't remember the lesson after I learned it.
a. to go 
Mi abuelo se quedó ciego cuando tenía 80 y pico años.My granddad went blind when he was 80 something.
13. (colloquial) (to trick) (Spain)
A word or phrase that is commonly used in conversational speech (e.g., skinny, grandma).
Regionalism used in Spain