Reset a combo box

Hi guys,

I have a small issue that I would like to correct. What script can reset a combobox ? After the user submitted the form all the information needs to go. I found how to do it for the field text and the checkboxes but not how to reset the combobox.

e.g. working;
txtfirst.text = “”;
workshop1_box.selected = false;

combobox = ???

Thanks in advance !!!