The meaning of identification of ancient comets is summarized: it is useful to study a long-term evolution of short- period comets and chronology.是什么意思_The meaning of identification of ancient comets is summarized: it is useful to study a long-term evolution of short- period comets and chronology.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句