switch留个爪，之后还需要再研究下

public class SwitchDemo
{
    public static void main (String [] args)
    {
        for(int i = 0; i < 10; i++)
        {
            char c = (char) (Math.random() * 26 + 'a');
            System.out.print (c + ": ");
            switch (c)
            {
                case 'a':
                case 'e':
                case 'i':
                case 'o':
                case 'u':    
                        System.out.println("vowel");
                        break;
                case 'y':
                case 'w':
                        System.out.println("Sometimes a vowel");
                        break;
                default:
                        System.out.println("consonant");}
        }
    }
}