求告诉，哪错了

Question

#include <stdio.h>

int main() 

{ 

    /* 定义需要计算的日期 */

    int year = 2008;

    int month = 8;

    int day = 8;

     int date=0;

    switch(month)

    {

    case 1:date+=31;

    case 2:if(year%4==0){

        date+=29;

    }else{

        date+=28;

    };

    case 3:date+=31;

    case 4:date+=30;

    case 5:date+=31;

    case 6:date+=30;

    case 7:date+=31;

    case 8:date+=31;

    break;

    }

    date=date+day;

    printf("%d年%d月%d日是该年的第%d天",year,month,day,date);

return 0;

}