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"Las guías" is a form of "guía", a noun which is often translated as "guide". "Los" is a definite article which is often translated as "the". Learn more about the difference between "los" and "las guías" below.
los(
lohs
)A definite article is a word that identifies a noun as specific or known to the speaker (e.g., the girl).
A pronoun is a word that stands in for a noun (e.g., she).
el guía, la guía(
gee
-
ah
)This means that the noun can be masculine or feminine, depending on the gender of the noun it refers to (e.g., el doctor, la doctora).
1. (profession)
a. guide 
Tuvimos que cancelar la excursión porque nuestro guía se enfermó.We had to cancel our hike because our guide got sick.
A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
b. map  (of streets)
No estaría de más tener una guía de la ciudad.It might help to have a map of the city.
c. handbook  (of a piece of furniture or a device)
Lea las instrucciones de la guía antes de montar el armario.Read the instructions in the handbook before mounting the closet.
3. (mechanics)
a. guide 
Abre y cierra la puerta para asegurarte de que se deslice sin problemas por la guía.Open and close the door to make sure that it slides freely along the guide.
a. guidance 
Estos resultados ofrecen una guía útil para futuros estudios sobre el tema.These findings offer useful guidance for future studies on the topic.
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
a. steering wheel  (a car)
Recuerda siempre mantener las manos en el guía.Remember to always keep your hands on the steering wheel.
b. handlebars  (a bicycle)
Giró el guía para evitar otro ciclista.He swerved the handlebars to avoid another biker.