function checkForm(form) {
	
	 if (form.name.value == '') {
        alert("Name field is empty");
        form.name.focus();
        return false;
    }
	
	if (form.email.value == '') {
        alert("Email field is empty");
        form.email.focus();
        return false;
    }
	
	if (form.zip.value == '') {
        alert("Zip Code field is empty");
        form.zip.focus();
        return false;
    }
	
	if (form.comments.value == '') {
        alert("Comments field is empty");
        form.comments.focus();
        return false;
    }
	
    return true;
}