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"Aconsejar" is a transitive verb which is often translated as "to advise", and "necesitar" is a transitive verb which is often translated as "to need". Learn more about the difference between "aconsejar" and "necesitar" below.
aconsejar()
A transitive verb is a verb that requires a direct object (e.g., I bought a book.).
1. (to suggest)
a. to advise
Las autoridades aconsejan no salir durante la tormenta.Authorities advise against going outside during the storm.
b. to recommend
El médico le aconsejó reposo para curar su lesión de rodilla.The doctor recommended rest to help his knee recover.
a. to make advisable
La gran afluencia de turistas aconseja restringir la entrada al parque.The huge tourist influx makes limiting access to the park advisable.
aconsejarse
A pronominal verb always uses a reflexive pronoun. (e.g., Te ves cansado.).
necesitar()
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.