Examples

Cardinal Ordinal Cardinal Ordinal
one first twenty-one twenty-first
two second twenty-two twenty-second
three third twenty-three twenty-third
four fourth twenty-four twenty-fourth
five fifth twenty-five twenty-fifth
six sixth twenty-six twenty-sixth
seven seventh twenty-seven twenty-seventh
eight eighth twenty-eight twenty-eighth
nine ninth twenty-nine twenty-ninth
ten tenth thirty thirtieth
eleven eleventh thirty-one thirty-first
twelve twelfth thirty-two thirty-second
thirteen thirteenth thirty-three thirty-third
fourteen fourteenth thirty-four thirty-fourth
fifteen fifteenth thirty-five thirty-fifth
sixteen sixteenth thirty-six thirty-sixth
seventeen seventeenth thirty-seven thirty-seventh
eighteen eighteenth thirty-eight thirty-eighth
nineteen nineteenth thirty-nine thirty-ninth
twenty twentieth forty fortieth