The reason why BBK learning machine only has Chinese and no mathematics is because the mathematics teaching materials are not downloaded into the learning machine. Click Download on BBK official website homepage and select Data Download. After entering the page, it shows that BBK learning machine can download materials including Chinese, mathematics and English *** 17, including all textbooks from primary school to high school to adult college entrance examination. There is a math class, just download it to the learning machine when you study. Therefore, the reason why BBK learning machine only has Chinese and no mathematics is that the mathematics textbook has not been downloaded to the learning machine.