 |
| |||
| hierarchy | |||
| hierarchy configuration | |||
| hierarchic structure | |||
| hierarchical structure | |||
| 分级 结 构: 40 phrases in 10 subjects |
| Animal husbandry | 1 |
| Aviation | 2 |
| Cartography | 1 |
| Desert science | 1 |
| Electronics | 10 |
| Hydroelectric power stations | 1 |
| Project management | 1 |
| Space | 6 |
| Technology | 15 |
| Telecommunications | 2 |