<sequential>
    <vertical>
        <poll_question id="first_poll" display_name="first poll">
                <h3>What's the Right Thing to Do?</h3>
                <p>Suppose four shipwrecked sailors are stranded at sea in a lifeboat, without
    food or water. Would it be wrong for three of them to kill and eat the cabin
    boy, in order to save their own lives?</p>
            <answer id="Yes">Yes</answer>
            <answer id="No">No</answer>
            <answer id="Dont_know">Don't know</answer>
        </poll_question>
        <poll_question id="second_poll" display_name="second poll">
                <h3>What's the Right Thing to Do?</h3>
                <p>Suppose four shipwrecked sailors are stranded at sea in a lifeboat, without
    food or water. Would it be wrong for three of them to kill and eat the cabin
    boy, in order to save their own lives?</p>
            <answer id="Yes">Yes</answer>
            <answer id="No">No</answer>
            <answer id="Dont_know">Don't know</answer>
        </poll_question>
    </vertical>

    <wrapper>
        <!-- Test many show tags -->
        <html>Condition: first_poll - Yes</html>
        <conditional sources="i4x://HarvardX/ER22x/poll_question/first_poll" poll_answer="Yes">
            <html>In first condition.</html>
            <show sources="i4x://HarvardX/ER22x/poll_question/second_poll"/>
        </conditional>
    </wrapper>
</sequential>
