twenty---twentieth 　　twenty-one---twenty-first 　　twenty-two---twenty-second 　　twenty-three---twenty-third 　　twenty-four---twenty-fourth 　　twenty-five---twenty-fifth 　　twenty-six---twenty-sixth 　　twenty-seven---twenty-seventh 　　twenty-eight---twenty-eighth 　　twenty-nine---twenty-ninth 　　thirty---thirtieth 　　thirty-one---thirty-first