How old is the third set of four-level prescribed movements suitable for mass aerobics?
* * * There are six levels, one, two, three are elementary, and there are routines for adults and children. The first and second levels are mainly for beginners in primary and secondary schools, and the third level is mainly for beginners in colleges and universities. The document stipulates that you can't skip the exam, and the fourth and fifth grades are intermediate. Generally, after the third grade, you can study for the exam in the fourth grade. Level 6 is advanced.