1. 您好，先将您的第二个选择ID从'select01'更改为'select02'-ID应该是唯一的
2. 包括jquery

3. 添加脚本

1. Hi first change your second select id from 'select01' to 'select02' - ids should be unique
2. include jquery

3. add the script

    $(document).ready(function(){
        $('#select01').bind('change', function(){

            $('#select02 option').remove();

            switch($(this).val()) {
            case 'EDMATH 502':
                $('#select02').append('<option value="647abf63-fd95-42a7-a744-e1885f8d5c16">photoshop</option>');
                $('#select02').append('<option value="0f53de4a-1bb6-43bd-a567-fe181b25cfbe">matlab</option>');
                $('#select02').append('<option value="647abf63-fd95-42a7-a744-e1885f8d5c16">photoshop</option>');
                $('#select02').append('<option value="0f53de4a-1bb6-43bd-a567-fe181b25cfbe">matlab</option>');
                break;
            case 'EDTECH 401':
                $('#select02').append('<option value="test1">test1</option>');
                $('#select02').append('<option value="test2">test11</option>');
                break;
            case 'Math 101':
                $('#select02').append('<option value="test2">test2</option>');
                $('#select02').append('<option value="test22">test22</option>');
                break;
            }



        })
    });