Some galaxies recede from us at 1,000 kilometers per second, others (those twice as distant) at 2,000 km/s, and so on.是什么意思_Some galaxies recede from us at 1,000 kilometers per second, others (those twice as distant) at 2,000 km/s, and so on.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句