While unscrewing the injector button head, a second wrench must be used to assure that the injector body is not loosened from the main valve.是什么意思_While unscrewing the injector button head, a second wrench must be used to assure that the injector body is not loosened from the main valve.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句