a program of rocket-powered flights undertaken by US between 1961 and 1963 with the goal of putting a man in orbit around the earth是什么意思_a program of rocket-powered flights undertaken by US between 1961 and 1963 with the goal of putting a man in orbit around the earth在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句