Dynamic Drop-down change form

Hi there,

I have a web form, includes 3 dropdown fields called “Course name”, “Course date”, “Cost”. Only the first dropdown will have the items added selectable (Course name).

For example, the “Course Date” will be selectable if an option value of “Course Name” is selected, the “Cost” will be selectable if an option value of “Course date” is selected.

I don’t know if Contact For 7 supports this feature, please help.

Here is my code (not working)
<div class=”flexible”>
<p>Course:<br />[select* course-name “Please select a course” “C-Bus Intro Course” “Leviton Intro Course” “Environexus Intro Course” “Optic Firbe Basics Course” “Lilin IP CCTV Intro Course”]</p>
<p>Date:<br />[select* date-course “Please select a date” “14th Sep, 2016” “21st Sep, 2016” “27th Sep, 2016” “11th Oct, 2016” “26th Oct, 2016” “10th Nov, 2016” “16th Nov, 2016” “29th Nov, 2016” “6th Dec, 2016” “14th Dec, 2016”]</p>
<p>Cost:<br />[select* cost-course “How much does it cost?” “$50” “$60” “$100” “$150” “$1,218.34”]</p>
</div>

Really appreciate