protected function _prepareForm()
{
/** @var \Magento\Framework\Data\Form $form */
$form = $this->_formFactory->create(['data' => ['id' => 'edit_form', 'action' => $this->getData('action')]]);
$thesaurusTypes = [['value' => ThesaurusInterface::TYPE_SYNONYM, 'label' => __('Synonym')], ['value' => ThesaurusInterface::TYPE_EXPANSION, 'label' => __('Expansion')]];
$fieldset = $form->addFieldset('base_fieldset', ['legend' => __('Type')]);
$fieldset->addField('type', 'select', ['name' => 'type', 'label' => __('Thesarurus Type'), 'title' => __('Thesarurus Type'), 'values' => $thesaurusTypes]);
$form->setUseContainer(true);
$this->setForm($form);
return parent::_prepareForm();
}