Zhenyu Cheng

GSL（General Service List）是由国际知名英语专家组成的项目组研发。这些词汇成为初级基础英语材料用词的主流。备考雅思及其他英语考试，掌握GSL词汇是最基本的要求。亮点：单词发音 &

Understand Alphabet has 52 amazing and beautiful pictures of letter which engages the child's at

Understand Numbers has 101 amazing and beautiful pictures of number which engages the child's at