one - first - 1st
two - second - 2nd
three - third - 3rd
four - fourth - 4th
five - fifth - 5th
six - sixth - 6th
seven - seventh - 7th
eight - eighth - 8th
nine - ninth - 9th
ten - tenth - 10th
eleven - eleventh - 11th
twelve - twelfth - 12th
thirteen - thirteenth - 13th
fourteen - fourteenth - 14th
fifteen - fifteenth - 15th
sixteen - sixteenth - 16th
seventeen - seventeenth - 17th
eighteen - eighteenth - 18th
nineteen - nineteenth - 19th
twenty - twentieth - 20th
twenty-one - twenty-first - 21st
thirty - thirtieth - 30th
forty - fortieth - 40th
fifty - fiftieth - 50th
sixty - sixtieth - 60th
seventy - seventieth - 70th
eighty - eightieth - 80th
ninety - ninetieth - 90th
hundred - hundredth - 100th
etc.
* * *