récurrence: 68 phrases in 17 subjects |
Astronautics | 7 |
Astronomy | 3 |
Automated equipment | 1 |
Aviation | 5 |
General | 1 |
Geology | 1 |
High energy physics | 1 |
Hydraulic engineering | 1 |
Information technology | 6 |
Mathematics | 19 |
Mechanic engineering | 2 |
Military | 1 |
Natural resourses and wildlife conservation | 2 |
Radio | 6 |
Statistics | 2 |
Technology | 6 |
Радиоактивное излучение | 4 |