function validate() {
  if (document.send.name.value == "" || document.send.subject.value == "" || document.send.message.value == "") {
    alert ("Please fill in your name, subject and message.");
    return false;
  } 
  if (document.send.email.value == "" || document.send.phone.value == "") {
    alert ("Please fill in at least one of Email and Phone.");
    return false;
  }
  else {
    return true;
  }
}