1·They are the stairs in the main building.
这是主楼的楼梯。
2·They decided to cover in the passage between the main building and the annex.
他们决定在主楼与附属建筑物之间的过道上面加盖屋顶。
3·It was also designed to include a theater, recording studios and cinemas, while CCTV's main production and broadcasting units were to occupy the main building next door.
同时被设计的还包括剧场、录音室和电影院，而CCTV的主要制作和播放部门则占用了隔壁的主楼。
4·CCTV's main production and broadcasting units are expected to occupy the main building next door.
预计央视主要的制作和广播部门将使用隔壁的主楼。
5·But three of them changed their minds on their way and ran back to the main building, and they're missing now.
但是其中三人在逃跑的途中改变主意，回到主楼，现在他们已经失踪。