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频率变换; 变频 | |||
频率变化 | |||
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变〔换〕频; 频率变换 |
frequency- change : 21 phrases in 11 subjects |
Air defense | 2 |
Animal husbandry | 1 |
Automobiles | 1 |
Aviation | 3 |
Electric machinery | 2 |
Genetics | 2 |
Information technology | 1 |
Metallurgy | 2 |
Military | 1 |
Technology | 4 |
Telecommunications | 2 |