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"Necesita" is a form of "necesitar", a transitive verb which is often translated as "to need". "Es preciso" is a phrase which is often translated as "it's necessary". Learn more about the difference between "necesita" and "es preciso" 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.).
a. to need
Necesitan salir ya si quieren alcanzar su vuelo.You need to leave now if you want to make your flight.
es preciso(
ehs
preh
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see
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soh
)A phrase is a group of words commonly used together (e.g., once upon a time).
a. it's necessary
Es preciso reducir la contaminación en las grandes ciudades.It's necessary to reduce pollution in big cities.
b. it's essential
Es preciso tener una buena conexión a Internet para el teletrabajo.It's essential to have a good Internet connection for teleworking.
c. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
El informe estará listo mañana. Trabajaré toda la noche si es preciso.The report will be ready tomorrow. I'll work all night if necessary.
Es preciso que intervengas. Tú eres la jefa y a ti te respetan.You have to intervene. You're the boss and they respect you.