Ответ:

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