Training steps 1. The trainer should wear red-rimmed glasses and hold the card at a distance of 40cm from the eyes. 2. At this time, the left eye (green piece) can see the pink letters on the white background plate, and the right eye can see the black letters on the red background plate, then use the left eye to read the letters on the white background plate, and use the right eye to read the letters on the red background plate. Put the small card in the near place (40cm from the eyes) and then put the big card in the far place (3m from the eyes). 4. Training sequence and training method, refer to the alphabet training method.