Числа от $0$ до $20$ по-английски:
$0$ — zero
$1$ — one
$2$ — two
$3$ — three
$4$ — four
$5$ — five
$6$ — six
$7$ — seven
$8$ — eight
$9$ — nine
$10$ — ten
$11$ — eleven
$12$ — twelve
$13$ — thirteen
$14$ — fourteen
$15$ — fifteen
$16$ — sixteen
$17$ — seventeen
$18$ — eighteen
$19$ — nineteen
$20$ — twenty