mierEdu English Brain Puzzle consists of five different levels with learning target of 26 letters and more than 100 common words. mierEdu follows the phonics rule: letter sound, short vowels, long vowels, consonant blends, and letter combinations. To help children improve early reading skills through the puzzle game step by step. Word spelling made simple just complete the picture. Meanwhile all mierEdu products are made of eco-friendly materials, which brings your kids a safe and healthy playtime, ensures sustainable development for the planet.