Apps suitable for four-year-old children, such as one-on-one teaching of Dada English, four-in-one listening, speaking, reading and writing for foreign teachers in Europe and America, establish English thinking, live mobile phone interaction and diverse and interesting classrooms. For example, there is a chattering course, and this software is a software that children use more. There is also a word learning platform for children who like English every time. Through this software, users can be more suitable for children to learn.