I see here that there is no option for kanji/kana ->Fill in the Blank (definition) option. I would love to have one. I don't trust myself with multiple choice. would that be hard to implement or is there a reason why it doesn't exist already?
Unfortunately, there is not a way to reliably check it through the site, which would leave it up to the user to mark it right or wrong.
For multiple choice, if you don't "trust yourself", I'd recommend hiding the answers, making a guess before you reveal them, then not allowing yourself to change your answer once they've been shown.