laravel5 中 关联查询

Question

有这么一组数据一个学生表users和学生成绩表grades两个表关联在方法里面是这样的publicfunctionindex(){$result=User::where('is_admin',0);$users=$result->get();$count=$result->count();returnview('admin.list',compact('count','users'));}视图循环是这样的@foreach($usersas$user){{$user->id}}{{$user->name}}{{$user->grade->math}}{{$user->grade->english}}{{$user->grade->c}}{{$user->grade->sport}}{{$user->grade->think}}{{$user->grade->soft}}@endforeach得到的结果是报错Tryingtogetpropertyofnon-object(View:$user->grade->math是找不到的怎么做关联一起呢