“You” works the same way, for the same reason: originally it was only plural (and “you” started to be used as a singular later than “they”). Notice “skate” ver

“You” works the same way, for the same reason: originally it was only plural (and “you” started to be used as a singular later than “they”). Notice “skate” versus “skates” in these cases: - Alice skates; Alice is a skater. - Alice and Bob skate; Alice and Bob are skaters. - She skates; she is a skater. - You skate; you are a skater. - You skate; you are skaters. - They skate; they are a skater. - They skate; they are skaters.