 |
| |||
| 信号维修 | |||
| signal maintenance: 17 phrases in 9 subjects |
| Air defense | 1 |
| Aviation | 3 |
| Communications | 3 |
| Electronics | 2 |
| General | 1 |
| Rail transport | 1 |
| Shipbuilding | 1 |
| Technology | 2 |
| Telecommunications | 3 |
|
| |||
| 信号维修 | |||
| signal maintenance: 17 phrases in 9 subjects |
| Air defense | 1 |
| Aviation | 3 |
| Communications | 3 |
| Electronics | 2 |
| General | 1 |
| Rail transport | 1 |
| Shipbuilding | 1 |
| Technology | 2 |
| Telecommunications | 3 |