选择：Many things () impossible in the past are quit common tod

选D,因为这是一个简单句,只能有一个谓语,Many things 是主语,are是谓语,common 是表语应该.considered impossible in the past 是做Many things 的后置定语,意思是说,过去许多被认为不可能的事情现在都很平常了.B表示将来不选,C表示主动,不是这件事认为,而是这件事被认为
in the past 要用一般式,不选A
这里其实可以改成一个定语从句；Many things that was considered impossible in the past are quit common today