--- /dev/null
+/**
+ * Implements hook_form_BASE_FORM_ID_alter().
+ */
+function {{ machine_name }}_form_BASE_FORM_ID_alter(&$form, \Drupal\Core\Form\FormStateInterface $form_state, $form_id) {
+ // Modification for the form with the given BASE_FORM_ID goes here. For
+ // example, if BASE_FORM_ID is "node_form", this code would run on every
+ // node form, regardless of node type.
+
+ // Add a checkbox to the node form about agreeing to terms of use.
+ $form['terms_of_use'] = [
+ '#type' => 'checkbox',
+ '#title' => t("I agree with the website's terms and conditions."),
+ '#required' => TRUE,
+ ];
+}