求翻译：学校办学规模发展迅速，2004年当年招生九个班级，至2015年达到五十个班级，其中小学部30个各班级，初中部20个班级。是什么意思？

The rapid development of schools, school size, class of 2004 nine year enrollment to reach fifty classes in 2015, the Ministry of thirty (30) primary and secondary classes, 20 middle school classes.

Scale of running schools, rapid development during the year 2004, a Class 9 for admission to the year 2015, which amounted to 50 classes of primary schools, 30 middle-class 20 classes.

The school scale of study programs development is rapid, in 2004 recruited students in the past nine classes and gradees, achieved 50 classes and gradees to 2015, in which elementary school department 30 various classes and gradees, initially middle 20 classes and gradees.

Rapid development of the school's size, enrollment nine classes of year 2004, between 2015 and up to 50 classes, of which 30 for each class in primary schools, junior high schools, 20 classes.

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