In the app (and also on the website) you can start learning again cards that already were completely learned. In tghose cases you would go trough the complete learning cycle for them.
Alternatively after logging into trainchinese.com you can select learned cards (from the Vocab lists) then press the and review them one time. (That button is visible if you first select the "...More" button on top of the list)
Answered 8 months ago by klaus