ShenzhouⅦmissionisacriticalstepinProject921,
China'smannedspaceprogram.ThelasttimeChinahad
sentamaninspacewasin2005.Itnowplansto
buildaspacelabcomplexaftertwoyears.ShenzhouⅦ,
thefirstChinesespacemissionwithfullcrew,which
seeksnotonlyconductthecountry'sfirstspacewalk,
butalsooffersimportanttechnicalpointsofreference
forfuturemissions.By2010,twounmannedaircraftsand
othermannedspaceshipwithacrewofthreewillstartwork
onChina'sfirstspacelab,completedthesecondphaseof
thethreestageProject921.
英语改错,最后一行不用改,前面10行有9行都是错了一处的.求改.