"Nosotros nos lavamos el cabello a menudo."
Translation:We wash our hair often.
Shouldn't it be "Nosotros lavamos nuestro cabello a menudo"? What's the difference?
Whenever you're washing yourself (as opposed to another object like the dishes or the car), "lavar" is reflexive so you must the appropriate reflexive pronoun.
In other words:
I wash (myself) = Me lavo
You (informal) wash (yourself) = Te lavas
He/she/you (formal) wash = Se lava
We wash (ourselves) = nos lavamos
They/Y'all wash (themselves/yourselves) = se lavan https://www.spanishdict.com/guide/reflexive-verbs-and-reflexive-pronouns
Also, in Spanish, names of parts of the body are frequently preceded by the definite article (el, la, los or las, meaning "the") instead of possessive adjectives (such as mi for "my" and tu for "your"). In most cases, the possessive adjective is used only where the context doesn't make clear whose body is being referred to.