i1yas

function replace($text, $word, $replacements) {
      $r = $replacements;
      $new_text = $text;
      $replacement = null;
      $pattern = "/$word/";
  
      while(true) {
          $replacement = $r[0];
  
          $new_text = preg_replace(
              $pattern,
              $replacement,
              $new_text,
              1, // заменяем 1 раз
              $count
          );
  
          if(!$count) return $new_text;
  
          // ротируем замены
          $r = array_merge(array_slice($r, 1), [$replacement]);
      }
  }

$replaced = replace(
      "First word. Second word. Third word. Forth word.",
      "word",
      ["apple", "banana", "watermelon"]
 );
print_r($replaced);
// First apple. Second banana. Third watermelon. Forth apple.

document.getElementById('find').value = result.textContent;