第一到第二十的英文是：

1first, 2second, 3third, 4fourth, 5fifth, 6sixth, 7seventh, 8eighth, 9ninth, 10tenth, 11eleventh, 12twelfth, 13thirteenth, 14fourteenth, 15fifteenth, 16sixteenth, 17seventeenth, 18eighteenth, 19nineteenth, 20twentieth