My question: If I know the right translation which button I have to use: "No need to review" or "I knew it"
The five options for answering are graduated. No need to review -> I presume the expression will never come back. I knew it -> I take it as "I knew it but I wouldn't mind getting it again one of these days." ... ... I didn't know -> I noticed it showed up in the very next lesson.
Hallo Bernd, it depends on your desire to meet the words again. If you're a surgeon you surely aren't too fond of medical vocabulary. If you are an accounter you certainly need the special accounting vocabulary just once. But as a journalist, an artist, a child, a story teller you're perhaps so interested in all fields of life, that you would like to read the words again and again after weeks or months, enjoying the fact that you always know the right translation.