"Your shirts are black."

[jloibman]

Votre is not the same as Vos?

[jordanque]

votre is singular vos is plural like vos chemises, votre chemise

[E.T.s_Son]

I thought "Vos" would be a correct answer as well

[NavGirdhar]

"Vos chemises sont noires" is also right answer. :-)

[countryred]

Chemises is plural

[SiddharthPrabhu]

Why is "Tes chemises sont noirs" incorrect?