一、单数、复数 is(复数)are am(复数)are are(单数)is library(复数)libraries slory(复数)stories factory(复数)factories body(复数)bodies hobby(复数)hobbies people(复数)people fish(复数)fish milk(复数)milk juice(复数)juice bread(复数)bread water(复数)water riee(复数)rice policeman(复数)policemen policewoman(复数)policewomen fireman(复数)fremen firewoman(复数)firewomen
