Why would things weigh only a quarter as much as they do at the surface of the earth if we took them 4,000 miles out into space ?是什么意思_Why would things weigh only a quarter as much as they do at the surface of the earth if we took them 4,000 miles out into space ?在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句