It was the first of several orbiters that are surveying the cold, barren lannscape, looking especially for signs of water, and relaying signals from the two robotic rovers crawling over the terrain.是什么意思_It was the first of several orbiters that are surveying the cold, barren lannscape, looking especially for signs of water, and relaying signals from the two robotic rovers crawling over the terrain.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句