1- first
2- second
3- third
4- fourth
5- fifth
6- sixth
7- seventh
8- eighth
9- ninth
10- tenth
11- eleventh
12- twelfth
13- thirteenth
14- fourteenth
15- fifteenth
16- sixteenth
17- seventeenth
18- eighteenth
19- ninteenth
20- twentieth
21- twenty-first
22- twenty-second
23- twenty-third
24- twenty-fourth
25- twenty-fifth
26- twenty-sixth
27- twenty-seventh
28- twenty-eighth
29- twenty-ninth
30- thirtieth
31- thirty-first
.....continue in same way (thirty-....)
40- fortieth
41- forty-first
...continue in same way (forty-....)
50- fiftieth