I'm just wondering it they would accept, *"Your students are miserable."
Isn't it "voster" instead of "vester"? By analogy with "noster". In Romanian they are nostru and vostru.
In Classical Latin it is vester; in Vulgar Latin it was voster by joint influence of noster and vos; the Romanic forms come from Vulgar Latin, obviously: Romanian vostru, Italian vostro, Fench votre, Spanish vuestro, Portuguese vosso.