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"Be" is a copular verb which is often translated as "ser", and "get used to" is an intransitive verb phrase which is often translated as "acostumbrarse a". Learn more about the difference between "be" and "get used to" below.
be(
bi
)A copular verb links the subject of a clause to the predicate (e.g., My brother is tall).
An intransitive verb is one that does not require a direct object (e.g., The man sneezed.).
An impersonal verb is a verb with no apparent subject (e.g., Llueve en España.).
An auxiliary verb, or helper verb, is a conjugated verb that comes before a main verb and determines the main verb's tense, mood, or aspect (e.g., I have gone.).
a.  no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
I'm going to the party. - So am I.Voy a la fiesta. - Yo también.
It is a lovely day, isn't it?Es un día precioso, ¿verdad?
a.  no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
I don't know how much salt is to be added to the sauce.No sé cuánta sal hay que añadir a la salsa.
The assignment is to be done by next Thursday.La tarea tiene que estar para el jueves que viene.
a.  no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
My baby is due in three months.Mi bebé nacerá dentro de tres meses.
Tomorrow, I'm going to the dentist.Mañana voy al dentista.
a.  no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
Had it not been for his family, he would have never become an artist.Si no fuera por su familia, nunca habría sido artista.
If I were you, I would not go.Yo en tu lugar, no iría.
get used to(  
giht
yust
tu
)An intransitive verb phrase is a phrase that combines a verb with a preposition or other particle and does not require a direct object (e.g., Everybody please stand up.).
a. acostumbrarse a 
I'm not sure I'll ever get used to the noise from the street.No estoy segura de que vaya a acostumbrarme al ruido de la calle.
b. habituarse a 
Eventually, you'll get used to the pace of this job.Eventualmente, te habituarás al ritmo de este trabajo.
A phrase is a group of words commonly used together (e.g., once upon a time).
2. (imperative)
a. acostúmbrate a  (informal) (singular)
A word or phrase used to refer to the second person informal “tú” by their conjugation or implied context (e.g., How are you?).
We're not going anywhere. Get used to it!No nos vamos a ir a ningún lado. ¡Acostúmbrate a ello!
b. habitúate a  (informal) (singular)
A word or phrase used to refer to the second person informal “tú” by their conjugation or implied context (e.g., How are you?).
Get used to the cold, or you'll never be happy in Detroit.Habitúate al frío. Si no, nunca estarás feliz en Detroit.