maintenance-free: 29 phrases in 16 subjects |
Accumulators | 1 |
Architecture | 1 |
Automobiles | 2 |
Aviation | 2 |
Business | 1 |
Chemistry | 1 |
Economy | 1 |
Electric machinery | 2 |
Electronics | 1 |
Hydroelectric power stations | 1 |
International trade | 2 |
Metallurgy | 1 |
Plastics | 1 |
Space | 2 |
Technology | 9 |
Textile industry | 1 |