一句改错,求教Exploration of the Solar System is continuing(/A),and
一句改错,求教
Exploration of the Solar System is continuing(/A),and at hte present rate of progress(/B) all the planets will habe been contacted within(/C) the near(/D) 50 years.
D有处错了,
有点拼写错误,Exploration of the Solar System is continuing(/A),and at the present rate of progress(/B) all the planets will have been contacted within(/C) the near(/D) 50 years.