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：

表示发生在谓语动词之前的动作时，应该用动词不定式的完成形式。句意为“据说在过去的几年里艾滋病对那个地区的男男女女来说是最大的挑战”。