<grammar xmlns="...">
  <rule id="yes">
    <one-of>
      <item>yes</item> <item>yeah</item> <item>you bet</item>
      <item xml:lang="fr">oui</item>
    </one-of> 
  </rule> 
  <rule id="no">
    <one-of>
      <item>no</item> <item>nope</item> <item>no way</item>
      <item xml:lang="fr">non</item>
      <item xml:lang="fr">pas question</item>
    </one-of>
  </rule>
  <rule id="answer" scope="public">  
    <one-of>
      <item> <ruleref uri="#yes"/> </item>
      <item> <ruleref uri="#no"/> </item>
    </one-of>
  </rule>
</grammar>