题目内容：

    The Chinese Lunar(月球) Exploration Program is designed to be conducted in three stages: The first is simply reaching lunar orbit(轨道), a task   1.(complete) by Chang‟e 1 in 2007 and Chang‟e 2 in 2010. The second is   2.(land) on the Moon, as Chang‟e 3 did in 2013 and Chang‟e 4 in 2019. The third one is collecting lunar samples and sending them to Earth, a task for the future Chang‟e 5 and Chang‟e 6 missions. It 3.(be) China‟s first sample return mission in December 2019.