NORAD, the North American Aerospace Defense Command, is a joint U.S.-Canadian agency in charge of aerospace control for the North American continent.是什么意思_NORAD, the North American Aerospace Defense Command, is a joint U.S.-Canadian agency in charge of aerospace control for the North American continent.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句