Groups seperateble: Easier maintences and management!
1). Manage Group{CreatorCEO + CFOs + HROs + CMOs + ...};
2). HorizontalLand Group;
3). Material Group;
4). VerticalLand Group;
5). Outside Decorate Group;
6). Inside Decorate Group;
7). Stair Group;
8). Lift Group;
9). Lady&Gentlman Room Group;
10). Window&Door Group;
11). Glass Cover Group;
12). LED Screen Group;
13). Electrical Group;
14). Water Group;
15). Gas Group;
16). Clean Group;
......
Seperateble can be not just inside but also outside!