填入适当的词使短文意思完整
People have looked at the moon and __76___poems for thousands of years,but nobody expected to go there _77_____1961 when Yuri Gagarin made the first manned space flight.Then the Americans decided to send a man to the moon. Apollo 11 took off on 16 July.The journey __78__four days.On 21 July Neil Armstrong _79___the first man to walk on the moon.There were six manned missions to the moon between 1969 and 1972.We’ve learnt a lot about the moon. Nothing has _80___ lived on the moon. Life on the moon won’t be easy. It will be difficult and erous.
76 ______ 77______78 ______79 ______ 80 ______