Поставьте существительные во множественное число: student, factory, volcano, sheep, bush, play, tooth, swine, water, knife, love, church, gold, fire-company, fish, woman-conductor, showgirl, fireman, child, boy, lamp, computer.

Students, factories, volcanoes, sheep, bushes, plays, teeth, swine, water, knives, loves, churches, golds, fire-companies, fishes, women-conductors, showgirls, firemen, children, boys, lamps, computers.