问题
选择题
__________ that these creatures are linked to a common ancestor.
A．As is believed
B．What is believed
C．That is believed
D．It is believed
答案
答案：D
题目分析：考查句型：It is believed that…，据相信…,it 是形式主语，that引导的是真正的主语，句意：据相信这些生物和一个共同的祖先有联系。选D。
点评：It is believed that…，据相信…这个句型可以改写成：Sb/sth is said to do句型，要学会互相转化，而且过去分词除了believed，还有said，thought，suggested等。