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"Cannot" is an auxiliary verb which is often translated as "no poder", and "must not" is a phrase which is often translated as "no deber". Learn more about the difference between "cannot" and "must not" below.
cannot(
kah
-
nat
)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.).
must not(
muhst
nat
)A phrase is a group of words commonly used together (e.g., once upon a time).
b. no hay que
We must not be too reckless, or our strategy will fail.No hay que ser demasiado imprudentes, o nuestra estrategia terminará en el fracaso.
a. no deber de
That guy is parking in front of a fire hydrant. He must not realize it's there.Ese tipo está estacionando delante una boca de incendios. No debe de darse cuenta de que está ahí.
