function ValidateForm(f){

            with(f){
         if (isEmpty(_1_Name.value)) {
            alert("Please enter your Name");
            _1_Name.focus();
            return false;
         }

         if (isEmpty(_2_Email_From.value)) {
            alert("Please enter your Email Address");
            _2_Email_From.focus();
            return false;
         }

         if ( !isEmail(_2_Email_From.value) ) {
            alert("Please enter a valid Email Address.");
            _2_Email_From.focus();
            return false;
         }

            if ( isEmpty(_3_Telephone.value) ) {
            alert("Please enter your Phone Number");
            _3_Telephone.focus();
            return false;
         }

         if (!isEmpty(_3_Telephone.value)) {
	         if (!IsNumber(_3_Telephone.value, true)) {
            	alert("Please enter only numbers for your Phone");
            	_3_Telephone.focus();
            	return false;
         	}
         }

		  if (isEmpty(_4_Comments.value)) {
            alert("Please enter your comments or enquiry");
            _4_Comments.focus();
            return false;
         }

   	}
   return true;
 }