I want the flash cards to be divided into three categories at the end: “Can I”, “Can I halfway” and “I can't.” Depending on which category you sort a card into, it should then be displayed again at different intervals. Cards from “Can I not” are particularly common, cards from “Can I” rather rarely. In addition, it should be possible to specifically select the stacks, such as “Can't I”, in order to practice it separately and more intensively.