var vowelDoubler = function(array) {
  var vowels = ['a', 'e', 'i', 'o', 'u'];
  var temps = [];
  var i = 0;
  while (i < array.length || temps.length !== 0) {
    if (array[i]) {
      temps.push(array[i]);
      if (vowels.includes(array[i])) {
        temps.push(array[i]);
      }
    }

    array[i] = temps.shift();
    i++;
  }
  return array;
};