语法分册的第33页的第9题

寂寞的自由

14．Astronomers at the Palomar Observatory have discovered a distant supernova explosion, one that they believe is a type previously unknown to science.  A---àE(A) that they believe is (B) that they believe it to be(C) they believe that it is of(D) they believe that is(E) they believe to be of

哪位朋友帮忙讲解一下，正确答案是E

深海的小美人鱼

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