程序代码：

#include <stdio.h>

int main(void)
{
    int ten_digit, sigle_digit;

    printf("Enter a two digit number: ");
    scanf("%d%d", &ten_digit, &sigle_digit);

    if (ten_digit == 1)
    {
        switch (sigle_digit)
        {
            case 0:
                printf("You enter the number ten");
                break;
            case 1:
                printf("You enter the number eleven");
                break;
            case 2:
                printf("You enter the number twelve");
                break;
            case 3:
                printf("You enter the number thirdteen");
                break;
            case 4:
                printf("You enter the number forteen");
                break;
            case 5:
                printf("You enter the number fifteen");
                break;
            case 6:
                printf("You enter the number sixteen");
                break;
            case 7:
                printf("You enter the number seventeen");
                break;
            case 8:
                printf("You enter the number eighteen");
                break;
            case 9:
                printf("You enter the number nineteen");
                break;
            default:
                break;
        }
    }

    else
    {
        switch (ten_digit)
        {
            case 2:
                printf("You enter the number twenty-");
                break;
            case 3:
                printf("You enter the number thirty-");
                break;
            case 4:
                printf("You enter the number forty-");
                break;
            case 5:
                printf("You enter the number fifty-");
                break;
            case 6:
                printf("You enter the number sixty-");
                break;
            case 7:
                printf("You enter the number seventy-");
                break;
            case 8:
                printf("You enter the number eighty-");
                break;
            case 9:
                printf("You enter the number nighty-");
                break;
            default:
                break;
        }

        switch (sigle_digit)
        {
            case 1:
                printf("You enter the number one");
                break;
            case 2:
                printf("You enter the number two");
                break;
            case 3:
                printf("You enter the number three");
                break;
            case 4:
                printf("You enter the number four");
                break;
            case 5:
                printf("You enter the number five");
                break;
            case 6:
                printf("You enter the number six");
                break;
            case 7:
                printf("You enter the number seven");
                break;
            case 8:
                printf("You enter the number eight");
                break;
            case 9:
                printf("You enter the number night");
                break;
            default:
                break;
        }
    }

    return 0;
}