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"Must" is an auxiliary verb which is often translated as "deber", and "be" is a copular verb which is often translated as "ser". Learn more about the difference between "must" and "be" below.
must(
muhst
)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.).
1. (obligation)
2. (suggestion)
3. (likelihood)
a. deber de
You must be very tired after your long drive.Debes de estar muy cansado después de manejar tanto.
A noun is a word referring to a person, animal, place, thing, feeling, or idea (e.g., man, dog, house).
a. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
Having a cell phone is a must nowadays.Hoy en día es indispensable tener un celular.
This album is a must for all fans of jazz music.Este es un álbum que no deben perderse todos los aficionados a la música jazz.
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.
