Tsinghua Children's English (preparatory level) is mainly aimed at children aged 3-6, effectively connecting the main textbook Tsinghua English, and extending the training scope of Tsinghua Children's English to children aged 3- 16. This new textbook is divided into three levels according to children's intellectual development and understanding ability at different ages, with a total of six volumes, namely doer A, doer B, explorer A, explorer B, thinker A and thinker B. Among them, doer level is suitable for children aged 3-4, explorer level is suitable for children aged 4-5 and thinker level is suitable for children aged 5-6.