The advanced input mode has the option to add a comment, visible after the answer is given during the test.
This can be a short explanation, but also a large text about the question and its answer.
If you enter a link to a website, this website will be displayed.
It is possible to show this info only if the answer is wrong.
It is possible to play a sound file after the question has been answered. This makes it possible to hear the pronunciation during the test.