function validateEmail(form1){      
       var emailPattern = /^[a-zA-Z0-9._-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,4}$/;
       return emailPattern.test(form1); 
   }
   function chkform(form1)
   {
	    if(document.form1.name.value=="")
    {
     alert("please enter your name");
     document.form1.name.focus();
     return false;
    }
	
    if(document.form1.email.value=="")
    {
     alert("please enter email address");
     document.form1.email.focus();
     return false;
    }
    if(!validateEmail(document.form1.email.value))
    {
     alert("please enter correct email address");
     document.form1.email.focus();
     return false;
    }
   
   if(document.form1.comments.value=="")
    {
     alert("please enter your Comments");
     document.form1.comments.focus();
     return false;
    }
    return true;
   }