My problem is that :I have found some codes.What can I do to run what i said things?And I want to when someone clicked menu item, it remove checkboxes values.(unchecked) My codes like that:\[code\]<html><head><title>Untitled Document</title><meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"><script src="http://ajax.googleapis.com/ajax/libs/jquery/1.3.2/jquery.js" type="text/javascript"></script><script type="text/javascript"> $(function(){ $(".form-row").hide(); $("#divListBox").find(":checked").each(function() { $(this).removeAttr("checked");}); $("#course_english").change(function() { if ($("#course_english").val() == "MA English") { $(".form-row").show(); } else { $(".form-row").hide(); } }); });</script></head><body><select id="course_english" class="" name="course_english"> <option value="">--Select One--</option> <option value="http://stackoverflow.com/questions/13735441/MA English">MA English</option> <option value="http://stackoverflow.com/questions/13735441/B. A. (Hons.) with Mass Communication">B.A. (Hons.) with Mass Communication</option> <option value="http://stackoverflow.com/questions/13735441/M. A. (English)">M. A. (English)</option> <option value="http://stackoverflow.com/questions/13735441/M. Phil.">M. Phil.</option> </select> <div class="form-row" id="divListBox"> <label for="sem_1_ma_english-poetry"> <input id="sem_1_ma_english-poetry" class="sem_1_ma_english" type="checkbox" value="http://stackoverflow.com/questions/13735441/Poetry" name="sem_1_ma_english[]">Poetry </label> <label for="sem_1_ma_english-drama"> <input id="sem_1_ma_english-drama" class="sem_1_ma_english" type="checkbox" value="http://stackoverflow.com/questions/13735441/Drama" name="sem_1_ma_english[]">Drama</label> <label for="sem_1_ma_english-fiction"> <input id="sem_1_ma_english-fiction" class="sem_1_ma_english" type="checkbox" value="http://stackoverflow.com/questions/13735441/Fiction" name="sem_1_ma_english[]"> Fiction </label> <label for="sem_1_ma_english-prose"> <input id="sem_1_ma_english-prose" class="sem_1_ma_english" type="checkbox" value="http://stackoverflow.com/questions/13735441/Prose" name="sem_1_ma_english[]"> Prose</label></div></body></html>\[/code\]