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"Llegar a ser" is a transitive verb phrase which is often translated as "to become", and "ponerse" is a reflexive verb which is often translated as "to get". Learn more about the difference between "llegar a ser" and "ponerse" below.
llegar a ser(  
yeh
-
gahr
ah
sehr
)A transitive verb phrase is a phrase that combines a verb with a preposition or other particle and requires a direct object (e.g., take out the trash.).
a. to become 
Nadie podía imaginar que una modesta maestra de escuela rural llegaría a ser la presidenta de la nación.No one could ever imagine that a modest rural schoolteacher would become the nation's president.
b. to get to be 
No llegarás a ser un buen pintor si no practicas mucho.You'll never get to be a good painter if you don't practice a lot.
c. to come to be 
Galván llegó a ser uno de los mejores actores de su generación.Galvan came to be one of the best actors of his generation.
d. to make it to 
No sé cómo un músico tan mediocre llegó a ser primer violín.I don't know how such a poor musician made it to first violin.
ponerse(
poh
-
nehr
-
seh
)A reflexive verb is a verb that indicates that the subject performs an action on itself (e.g., Miguel se lava.). 
1. (to become)
a. to get 
No te pongas impaciente conmigo cuando no has hecho nada para ayudar.Don't get impatient with me when you haven't done anything to help.
b. to be 
No te pongas triste, cariño. Todo se arreglará.Don't be sad, sweetie. Everything will work out.
c.  no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
Me pongo furiosa con pensarlo.It makes me mad to think about it.
El perro siempre se pone feliz al verte.The dog's always happy to see you.
a. to wear 
Ya nunca me pongo ese vestido porque se ha quedado muy anticuado.I don't wear that dress anymore because it's very old-fashioned.
6. (to go down)
poner
A transitive verb is a verb that requires a direct object (e.g., I bought a book.).
7. (to place)
8. (figurative) (to cause to be)
A phrase used as a figure of speech or a word that is symbolic in meaning; metaphorical (e.g., carrot, bean).
a. to put 
Su renuncia me pone en una situación difícil.His resignation puts me in a difficult position.
9. (clothing)
a. to put on 
Después de bañar a la bebé, hay que ponerle ropa limpia.After giving the baby a bath, you have to put some clean clothes on her.
10. (to install)
12. (to grade)
13. (to produce)
14. (to contribute)
a. to put in 
Podemos alquilar ese sitio si todos ponemos algo de dinero.We can rent the place if everybody puts in some cash.
15. (to connect)
16. (to name)
17. (to establish)
a. to open 
Sandy y su esposo van a poner una panadería en la calle principal.Sandy and her husband are going to open a bakery on main street.