Analysis and Calculation on Roof Separation Critical Values of Solid-coal Roadway and Gob-side Roadway Supported with Bolts是什么意思_Analysis and Calculation on Roof Separation Critical Values of Solid-coal Roadway and Gob-side Roadway Supported with Bolts在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句