序数词：
1.first,1st
2.second,2nd
3.third,3rd
4.fourth,4th
5.fifth,5th
6.sixth,6th
7.seventh,7th
8.eighth,8th
9.ninth,9th
10.tenth,10th
11.eleventh,11th
12.twelfth,12th
13.thirteenth,13h
14.fourteenth,14th
15.fifteenth,15th
16.sixteenth,16th
17.seventeenth,17th
18.eighteenth,18th
19.nineteenth,19th
20.twentieth,20th
21.twenty-first,21st
22.twenty-second,22nd
23.twenty-third,23rd
24.twenty-fourth,24th
25.twenty-fifth,25th
26.twenty-sixth,26th
27.twenty-seventh,27th
28.twenty-eighth,28th
29.twenty-ninth,29th
30.thirtieth,30th 序数词：
1.first,1st
2.second,2nd
3.third,3rd
4.fourth,4th
5.fifth,5th
6.sixth,6th
7.seventh,7th
8.eighth,8th
9.ninth,9th
10.tenth,10th
11.eleventh,11th
12.twelfth,12th
13.thirteenth,13h
14.fourteenth,14th
15.fifteenth,15th
16.sixteenth,16th
17.seventeenth,17th
18.eighteenth,18th
19.nineteenth,19th
20.twentieth,20th
21.twenty-first,21st
22.twenty-second,22nd
23.twenty-third,23rd
24.twenty-fourth,24th
25.twenty-fifth,25th
26.twenty-sixth,26th
27.twenty-seventh,27th
28.twenty-eighth,28th
29.twenty-ninth,29th
30.thirtieth,30th