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"Must not" is a phrase which is often translated as "no deber", and "cannot" is an auxiliary verb which is often translated as "no poder". Learn more about the difference between "must not" and "cannot" below.
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.
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.).
