title: Select all string in list and append a string - python
body: <p>I wanna add &quot;.&quot; to the end of any item of doing variable.
  and I want output like this =&gt; I am watching.</p>
  <pre><code>import random
  main = ['I', 'You', 'He', 'She']
  main0 = ['am', 'are', 'is', 'is']
  doing = ['playing', 'watching', 'reading', 'listening']
  rd = random.choice(main)
  rd0 = random.choice(doing)
  result = []
  '''
  if rd == main[0]:
      result.append(rd)
      result.append(main0[0])
  if rd == main[1]:
      result.append(rd)
      result.append(main0[1])
  if rd == main[2]:
      result.append(rd)
      result.append(main0[2])
  if rd == main[3]:
      result.append(rd)
      result.append(main0[3])
  '''
  result.append(rd0)
  print(result)
  </code></pre>
  <p>well, I tried those codes.</p>
  <pre><code>'.'.append(doing)
  '.'.append(doing[0])
  '.'.append(rd0)
  </code></pre>
  <p>but no one of them works, and only returns an error that:</p>
  <pre><code>Traceback (most recent call last):
    File &quot;c:\Users\----\Documents\Codes\Testing\s.py&quot;, line 21, in &lt;module&gt;
      '.'.append(rd0)
  AttributeError: 'str' object has no attribute 'append'
  </code></pre>