Question

The river is said __________ in a fire during the past 10 years.

1. A.
   to have polluted
2. B.
   it has been polluted
3. C.
   to pollute
4. D.
   to have been polluted

Answer 1

D
试题分析：考查句型：sb/sth is said to do/to have done,据相信某人/某物…，如果是将要做，用不定式一般式to do如果是已经做了，用不定式的完成式，句意：据说这条河在过去的10年里已经被污染了，用不定式完成式的被动，选D。
考点：考查固定句型
点评：固定句型是学习语言的重要环节。sb/sth is reported /believed to do/to have done,可以转化成It is reported /believed that句型，解答这类题目，关键是理解题干意思从而判断是动词不定式的什么形式，根据意思放入句子中进行比较，不难选出正确答案。