 |
| |||
| 变截面梁 | |||
|
variable section beam : 8 phrases in 4 subjects |
| Hydroelectric power stations | 2 |
| Rail transport | 1 |
| Space | 1 |
| Technology | 4 |
|
| |||
| 变截面梁 | |||
|
variable section beam : 8 phrases in 4 subjects |
| Hydroelectric power stations | 2 |
| Rail transport | 1 |
| Space | 1 |
| Technology | 4 |