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| observation | |||
| 观测'观察: 22 phrases in 10 subjects |
| Air defense | 1 |
| Aviation | 5 |
| Business | 1 |
| Earth sciences | 1 |
| Economy | 2 |
| Electronics | 2 |
| Mathematics | 2 |
| Navigation | 2 |
| Otorhinolaryngology | 2 |
| Technology | 4 |
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