互动封闭仿真课堂1、智能交互 2、电子板书式视频教学 3、5分钟一次互动问答 4、封闭课堂
The round stage is 20 meters in diameter and 1.7 meters high， with a circle of steps in the periphery.
The Main Stage is equipped with four rotating stairs and four round rotary elevating platforms 1.6 meters in diameter， the height of elevation being 2.8 meters.
Ten steel ropes are above the field， with a total weight of 40 tons.
Nineteen composers created 30 hours of music for the closing ceremony. A total of 600 hours was spent on the recording.
A total of 2，583 special lights are applied. The lighting equipments， weighing over 300 tons， were installed in five months.
Altogether there are 4，010 suits of costumes in 18 styles.
The rehearsal lasted 12 months. Volunteers began their first group rehearsal in September 2007.