If you want to learn the design of injection molding abrasives well, you should go to a technical school or a "Sunshine Project" training school designated by a government unit. This kind of school has rich and reasonable learning content and reasonable learning rhythm. The school will also arrange regular assessments for students.
Nanjing Kexun Education is only a training institution in society, providing training services for adults (excluding vocational certificate training approved by the state). Its training materials and teaching contents are formulated by its own institutions and are not representative.