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"Las mochilas" is a form of "mochila", a noun which is often translated as "backpack". "Ser" is a copular verb which is often translated as "to be". Learn more about the difference between "ser" and "las mochilas" below.
ser(
sehr
)A copular verb links the subject of a clause to the predicate (e.g., My brother is tall).
An intransitive verb is one that does not require a direct object (e.g., The man sneezed.).
a. to be made of
El casillero antiguo de mi abuela es de roble.My grandma's antique dresser is made of oak.
a. to root for
Yo soy del mejor equipo del mundo: FC Barcelona.I root for the best team in the world: FC Barcelona.
An impersonal verb is a verb with no apparent subject (e.g., Llueve en España.).
a. to be
Son las siete de la mañana.It is seven in the morning.
Era de noche cuando llegaron.It was night when they arrived.
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 be
El edificio fue diseñado por un equipo de arquitectos.The building was built by a team of architects.
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
la mochila(
moh
-
chee
-
lah
)A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
1. (knapsack)
a. backpack (United States)
Regionalism used in the United States
El libro está en mi mochila.The book is in my backpack.
b. rucksack (United Kingdom)
Regionalism used in the United Kingdom
Llenó la mochila de agua, papas y libros.She filled her rucksack with water, crisps, and books.
c. schoolbag
¡Cuánto pesa la mochila! ¿Tienes mucha tarea hoy?Your schoolbag is so heavy! Do you have a lot of homework today?
d. pack (for trekking or expeditions)
Los soldados llevaban sus mochilas encima de sus cabezas para que la lluvia no los mojara.The soldiers carried their packs over their heads so they didn't get wet in the rain.
