The verbs usar and utilizar mean exactly the same thing and are used in the same situations:
No uso crema solar = No utilizo crema solar
= I don't use sunscreen
¿Usas este abrigo o lo guardo? = ¿Utilizas
este abrigo o lo guardo? = Do you wear this coat or I’ll keep it?
La palabra "mamá" se usa sólo en familia = La palabra "mamá" se utiliza sólo en familia = The word mamá (mom) is used only in family
The verb usar is more frequent because it is shorter. Pay attention to the syntax: English expressions is used / are used must be translated into Spanish like se usa / se usan.
The verb emplear means the same, but it is more formal. It appears in technical or scientific texts, but never in spoken language:
El carbón se emplea para calentar la casa =
Coal is used to heat the house
El Futuro Simple se emplea para expresar la probabilidad =
Futuro Simple is used to express the probability
BUT: ¡No uses mis gafas! (Incorrect: noempleesmis gafas) = Don't wear my glasses
The verb servir can mean the same as
usarse, especially, with the preposition para:
– ¿Para qué sirve Facebook? = ¿Para qué se usa Facebook? = What is Facebook for?
– Para comunicarse con la gente = To communicate with people
Although syntactically it works in a different way, compare:
Esta caja me sirve para guardar cosas = Esta
caja la uso para guardar cosas = This box serves me to store things
¿Te sirve este abrigo? = ¿Usas este abrigo? = Do you wear this coat?
Unlike other verbs of this group, servir can be used with infinitives:
Discutir no sirve para nada = To argue is useless
(Incorrect: Discutir no *se usapara nada)