 |
| |||
| primary treatment | |||
| coarse purification; primary purification | |||
| первичная очистка: 18 phrases in 10 subjects |
| Aviation | 2 |
| Construction | 2 |
| Energy industry | 2 |
| Environment | 2 |
| Gas processing plants | 1 |
| Natural resourses and wildlife conservation | 3 |
| Oil / petroleum | 1 |
| Sakhalin | 1 |
| Technology | 2 |
| Water supply | 2 |