<input type="checkbox" name="stud" value="yes">Student
<input type="checkbox" name="lect" value="yes">Lecturer
<input type="checkbox" name="principal" value="yes">Principal 
<input type="checkbox" name="admin" value="yes">Administrator 
<input type="checkbox" name="parent" value="yes">Parent

<textarea name="txt" id="txt" rows="5" cols="100" class="text" mandatory='true' display='txt' pattern='ALPHA_NUMERIC_PLUS'><%=request.QueryString("txt")%></textarea>
 
function check(){
	document.form.action = "page.asp?txt="+document.form.txt.value;
	document.form.submit();
}

 <script language=javascript>
  function validate(){
   var email=document.forms[0].email.value;
   var comment=document.forms[0].comment.value;
   if(email==""||(email.indexOf('@')==-1)||(email.indexOf('.')==-1)){
    alert("E-mail field is invalid!");
    document.forms[0].email.focus();
    return false;
   }
   if(comment==""){
    alert("Comment field is empty!");
    document.forms[0].comment.focus();
    return false;
   }
   return true;
  }
 </script>
 
<form name="contact_form" method="post" action="http://..." onSubmit="return validate()">
 
<br>
<input type="submit" value="Submit">
<input type="reset" value="Reset">
</form>

 <script language=javascript>
  function validate(){
       var email=document.forms[0].email;
       if(email.checked!=true){
          alert("Email is not checked!");
          return false;
       }
       return true;
  }
 </script>