title: Optionality and "or" in capturing groups in perl
body: <p>I want to get a capturing group in a regex that has several "or"s and an optional group. This my my regex: <code>(a|e|i|o|u)?(a|e|i|o|u)(g|k)</code>
  I want it to find one or two vowels before a g or a k - like "taek" and "tag".</p>
  
  <p>I tried putting parenthesis around <code>(a|e|i|o|u)?(a|e|i|o|u)</code> but <code>$1</code> is still uninitialized.</p>