son estúpidas

are stupid

→ ser
phrase Rare #39,164
are stupid “Estúpidas” is the feminine plural form of “stupid” and agrees with a feminine plural subject.
SP: Tus excusas son estúpidas.
EN: Your excuses are stupid.

No todas las rubias son estúpidas.

Not all blondes are stupid.

Algunas personas no llevan careta porque son estúpidas e ignorantes.

Some people don’t wear face masks because they’re stupid and ignorant.

Tom piensa que las ideas de usted son estúpidas.

Tom thinks your ideas are stupid.

Las mujeres son estúpidas.

Women are stupid.

— Левиафан (2014)

Algunas personas no llevan mascarilla porque son estúpidas e ignorantes.

Some people don't wear masks because they're stupid and ignorant.

Tom piensa que las ideas tuyas son estúpidas.

Tom thinks your ideas are stupid.

Son estúpidas de veras, ¿verdad?

They’re really stupid, aren’t they?

Nadie quiere traducir sus frases porque son estúpidas.

Nobody wants to translate his sentences because they are stupid.