It is provided with a telescopic bracket.The box beam at the external side of the telescopic part of the bracket is inserted into the square hole in the main beam.是什么意思_It is provided with a telescopic bracket.The box beam at the external side of the telescopic part of the bracket is inserted into the square hole in the main beam.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句