Alotting values using typedef struct

Question

I'm having some issues using writing code using the type def statments in unison with the member access operator. I want to allot the value, see below, the my structure defined variables. But each time I give it a try I go further down the spiral and confuse myself. What am I doing wrong? Why won't this program print the different values?

#include <stdio.h>

void outputDate(courseInfo course);

typedef struct{
    int year;
    int month;
    int day;
}date;

typedef struct{
    double avrage;
    int students;
    date start;
    date end;

}courseInfo;

int main(void){

    courseInfo course;
    course.avrage = 10;
    course.students=200
    course.start={17,17,17};
    course.end={16,16,16};


    outputDate();

    return 0;
}

void outputDate(courseInfo course){
    printf("avrage%d\n", course.avrage);
    printf("students%d\n", course.students);
    printf("start%d\n", course.start);
    printf("end%d\n", course.end);
    return;
}

Answer 1

start is a structure, not an int , so using %d for the format code won't work.
Use something like
printf("start %d %d %d\\n", course.start.day, course.start.month, course.start.year);

Answer 2

除printf问题外，还应将路线变量传递给main中的outputDate（）函数。

outputDate(course);