//Question4 
correct = false;
System.out.println("how many feet are in a yard?");
while (!correct)
{
    x1 = input.nextInt();
    if (x1==3)
    {
        System.out.println("correct.");
        correct = true;
    }
    else
    {
        System.out.println("incorrect. try again.");
    }
}
    //Question5
correct = false;
System.out.println("What gets wetter and wetter the more it dries?");
while (correct == false)
{
   s1 = input.nextLine();
   if (s1.equalsIgnoreCase("a towel")) // cheating is bad!
    {
        System.out.println("correct");
        correct = true;
    }
    else
    {
        System.out.println("incorrect. try again.");
    }
}
输出 一码有多少英尺?3 正确。什么东西越干越湿? 不正确。再试一次。甚至在询问用户输入之前就被打印出来。