Special difficulties

好多动词后面既可以跟宾语从句，又可以和动词不定式to 搭配连用，其意义无差别。

打个比方：新概念英语怎么样

Instead of saying: I find that he is quite unsuitable for the job.

We can say: I find him to be quite unsuitable for the job.

常见的动词如下：

believe, consider, find, declare, feel, know, suppose, think, presume, estimate, understand

e.g. I consider that he is the best candidate. = I consider him to be the best candidate.

e.g. We estimated that this picture is worth at least 500 pounds. = We estimated this picture to be worth at least 500 pounds.