al world</span>
    </label>

    <label class="mdl-checkbox mdl-js-checkbox mdl-js-ripple-effect" for="checkbox-4">
      <input type="checkbox" id="checkbox-4" class="mdl-checkbox__input" />
      <span class="mdl-checkbox__label">Try using checkboxes</span>
    </label>

    <label class="mdl-checkbox mdl-js-checkbox mdl-js-ripple-effect" for="checkbox-5">
      <input type="checkbox" id="checkbox-5" class="mdl-checkbox__input" disabled />
      <span class="mdl-checkbox__label">But not this one</span>
 