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"Must" is an auxiliary verb which is often translated as "deber", and "shall" is an auxiliary verb which is also often translated as "deber". Learn more about the difference between "must" and "shall" 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.
shall(
shahl
)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 shan't tell you again.No pienso volver a decírtelo.
We shall see what happens.Veremos lo qué pasa.
a. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
Let's leave it for tomorrow, shall we?¿Lo dejamos para mañana?
Shall we invite them?¿Los invitamos?
3. (emphatic)
a. deber
The client shall make timely payments, or be charged penalties.El cliente deberá hacer pagos oportunos, o sufrirá recargos.
