- ALectureonSpaceFlight(一次航天飞行讲座)ALectureonSpaceFlightLastSaturdayIattendedalectureonspaceflight.IamgladthatIhavelearnedalotaboutspace.NowIknowsomethingaboutthestructureofaspacerocketandunderstandtheimportanceofspaceflighttomankind.Ibecomeinter...
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