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Both "necesita" and "necesito" are forms of "necesitar", which is often translated as "to need". Learn more about "necesitar" below.
necesitar(
neh
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seh
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see
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tahr
)A transitive verb is a verb that requires a direct object (e.g. I bought a book.).
1. (to require)
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.).
2. (to be necessary)
a. to need
Necesitan salir ya si quieren alcanzar su vuelo.You need to leave now if you want to make your flight.