_NAMES);

  // generate query text in the UI
  // d3.select('#query').html('Click on the link "' + correctText + '", and then enter "<span class="bold">' + q + '</span>" into the text field and press Submit.');
  d3.select('#query').html('Enter "<span class="bold">' + q + '</span>" into the text field and press Submit, after clicking on the link "' + correctText + '".');

  d3.select('#subbtn').on('click', function(){
    var t = d3.select('#tt')[0][0].value;
    var r = t === q ? 1.0 : -1.0;
    if (link_s