| |||
bituminous coal | |||
hard coal | |||
coal | |||
pit coal |
hulla : 58 phrases in 15 subjects |
Chemistry | 20 |
Coal | 8 |
Construction | 2 |
Energy industry | 6 |
Food service and catering | 1 |
General | 2 |
Health care | 4 |
Industry | 4 |
Materials science | 1 |
Metallurgy | 2 |
Mining | 1 |
Oil / petroleum | 1 |
Politics | 1 |
Statistics | 3 |
Technology | 2 |