◎ 题干
Earth is believed ______ by an object the size of Mars at some point in the distant past before itssurface cooled.
A.to be hit B.to have hit
C.to have been hit D.to hit
◎ 答案
查看答案
◎ 解析
查看解析
◎ 知识点
    根据魔方格专家分析,试题“Earth is believed ______ by an object the size of Mars at some point in the distant past before itssurface cooled.A.to be hitB.to have hitC.to have been hit D.t…”主要考查了你对  【现在分词的被动式】【现在分词】【不定式的被动式】【过去分词】  等知识点的理解和应用能力。关于这些知识点的“档案”,你可以点击相应的链接进行查看和学习。