Example

<vxml version="2.0" lang="en">
<form>

  <field name="city">
    <prompt>Where do you want to travel to?</prompt>
    <option dtmf="1">Edinburgh</option>
    <option dtmf="2">New York</option>
    <option dtmf="3">London</option>
    <option dtmf="4">Paris</option>
    <option dtmf="5">Stockholm</option>
  </field>

  <field name="travellers">
    <grammar type="application/srgs+xml" src="/grammars/number.grxml"/>
    <prompt>How many are travelling to <value expr="city"/>?</prompt>
  </field>

  <block>
    <submit next="http://localhost/handler" namelist="city travellers"/>
  </block>

</form>
</vxml>