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"Son las cuatro" is a phrase which is often translated as "it's four o'clock", and "treinta" is a noun which is often translated as "thirty". Learn more about the difference between "son las cuatro" and "treinta" below.
son las cuatro(
sohn
lahs
kwah
-
troh
)A phrase is a group of words commonly used together (e.g., once upon a time).
1. (general)
a. it's four o'clock
Son las cuatro de la tarde. Vamos a caminar al parque.It's four o'clock in the afternoon. Let's go for a walk in the park.
el treinta(
treyn
-
tah
)A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
2. (number)
b. thirtieth (in dates)
El cumpleaños de mi padre es el treinta de noviembre.My father’s birthday is on the thirtieth of November.