Dejar - meanings and expressions
We have a quick one today. 
These are the different combinations and meanings you need with dejar: 
Dejar combinations
1- Dejar de + inf 
To stop/quit doing something
Ex: Dejé de fumar hace dos años - I stopped smoking two years ago.
2- Dejar + somebody + inf 
To let or allow somebody do something 
Ex: Su madre no le deja salir hoy - Her mom doesn't let her go out today.
3- Dejar 
Leave (behind) or abandon
Ex: ¡No me dejés atrás! - Don't leave me behind!
Ex: Voy dejar un cepillo en tu casa -I'm going to leave a brush in your house.
4- Dejar algo a alguien 
To lend something to somebody
Ex: ¿Me dejas un boli? - Do you lend me a pen?
5- Dejarse 
To leave something behind not on purpose
Ex: Se dejó su abrigo en el restaurante - He left his coat in the restaurant.
or
To let yourself go /neglect appearance
Ex: Se ha dejado mucho ultimamemente - He's let himself go a lot lately.
Expresions
1- Dejarse barba /pelo largo /barriga... 
To grow a beard, long hair, belly...
Ex: Creo que Jesús va a dejarse barba - I think Jesús is going to grow a beard.
2- Dejar plantado/a 
To leave someone waiting, not show up
Ex: Estaba esperando y él me dejó plantada 
I was waiting and he left me waiting/he didn't show up.
3- Dejar tirado/a 
To abandon
Ex: Me ibas a ayudar pero me dejaste tirado 
You were going to help me but you abandoned me.
4- Dejar aparte 
To leave aside, ignore
Ex: Dejé esa información aparte porque no me pareció relevante 
I left that information aside because it didn't semem relevant to me.
5- Dejar atrás 
To leave behind or go past it
Ex: Tienes que dejarlo atrás 
You have to leave it behind.
Ex: Lo dejé atrás en la carrera 
I left him behind/went past him in the race.
6- Dejar caer 
To imply, to insinuate 
Ex: Dejé caer que sabía la historia 
I implied that I knew the story.
7- Dejarse caer (reflexive) 
To show up unexpected 
Ex: Lola se dejó caer por la tienda 
Lola showed up unexpected in the shop.
8- Dejar correr 
To allow, pretend to ignore 
Ex: No fui a clase pero la profesora lo dejó correr 
I didn't go to class but the teacher pretended not to know /allowed it.
9- Dejar vivir 
To let people be, not bother or interfere 
Ex: Tenéis que dejar vivir a vuestros hijos 
You guys have to let your children be.
10- Dejarse llevar (reflexive) 
To be weak, easily persuaded or to voluntarily let yourself go or do something 
Ex: Sabía que no era la mejor idea pero me dejé llevar 
I knew it wasn't the best idea but I let myself go/do it.
Ex: Lorena se deja llevar por los demás 
Lorena is easily persuaded by others.
Other alternatives of this one:
dejarse controlar - let one be controlled (by others)
Ex: Te dejas controlar por tu madre 
You let yourself be controlled by your mom
Aquí lo dejamos! - Here we leave it here! :)
¡Hasta la próxima!