Question

AIDS is said ________ the biggest health challenge to both men and women in that area over the past few years．

[　　]

A．that it is

B．to be

C．that is has been

D．to have been

Answer 1

答案：D
解析：

作定语或者宾语补足语用的不定式是考查的重点，但不定式在某些固定结构中的使用，包括它的语态和时态，也是近几年以来的考查重点，在平时做题的时候一定要注意总结积累。

提示：

…be said to do/be…这一结构我们在本单元中已经接触过，over the past few years经常与现在完成时连用，所以该题选用完成时的不定式。