1. Each question starts with 20 questions 2. A correct answer scores 5 out of 100 3. Once the question is answered, please press and hold the center of the screen to slide left up, right up, left down and right down to check the answer. 4. Release the screen to select the answer. 5. After 20 questions are answered, there will be a summary of the questions, convenient for you to check the wrong correction. This is a game I made for my son. He used to be good at pinyin, but not so good at addition under 20. After he tried the game, he became very interested in mathematics.He now gets full marks for adding up to 20 points at school. I am very happy and hope this game can bring you and your family happiness and achievement!