The trainer consists of five different boxes, each with different capacities.
The trainer works as follows: the vocabulary for each course is automatically loaded in Box 1. When you finish working on this vocabulary, the words you know will move to the next box, while the words you don't know will always remain in Box 1. As soon as Box 1 is empty, it will automatically fill up with new words.
Every time you want to learn vocabulary, the trainer will ask about the words in Box 1 first, unless another box is full. Once a word has run through all five boxes, it will be saved in the box marked “LEARNED”. That word is then saved in your long-term-memory!