function countChildElements(parent, child) {
  var parent = document.getElementById(parent);
  var childCount = parent.getElementsByTagName(child).length;

  switch(childCount) {
    case 0 : {
      document.write('No entries.');
      break;
    }
    case 1 : {
      document.write('One entry.');
      break;
    }
    default : {
      document.write(childCount.toString() + ' entries.');
      break;
    }
  } // end switch
}