根据惯用法，当动词think用来引导一个否定概念时，其后的that从句中的谓语动词不采用否定形式，通常是把主句的谓语动词think变成否定形式。如：I don’t think you’ve met my wife.（你大概没有见过我的妻子吧。）（不能说：*I think you haven’t met my wife.）但在下列情况，否定形式的位置须后移，即只能否定在think后面从句中的谓语动词上。

1. 当think以插入语形式出现时

    (1) I wish you were here, then I think I should not feel like this. 

       我希望你在这儿，这样我就不至于这样想你了。

(2) Conditions, I think, are not yet ripe for it. 

   我觉得条件还未成熟。

2. 当think以一般过去时（或过去进行时）的形式出现时

(1) I thought you didn’t want to hear, my dear. 

   亲爱的，我还以为你不想听哩。

(2) I was thinking that you wouldn’t be going with us. 

   我当时在想你不会和我们一道去的。

3. 当think以完成时（或完成进行时）的形式出现时

(1) I’ve often thought high life doesn’t agree with us. 

   我常常认为，奢侈的生活同我们是格格不入的。

(2) I have been thinking that Estella cannot be a condition of your inheritance, if she was never mentioned by your guardian. 

   我一直认为，如果你的保护人从来没有提到过埃斯特拉，那么她不可能成为你继承财产的条件。

4. 当think的前面有副词修饰，或者有强调作用的助动词do、does、did时

(1) You may be a clever man and a good teacher and all that, but I sometimes think you don’t see the simplest thing that is taking place under your very nose. 

   你也许是个聪明人，是位好老师，等等。不过我有时认为，就连发生在你眼皮底下的最简单的事情你也察觉不到。

(2) I do think you shouldn’t go there. 

   我的确觉得你不该去那里。

5. 当think和另一个动词构成并列谓语时

(1) I think and hope that I’m not disturbing you too much . 

   我想而且也希望我这样不会过分地打搅你吧。

(2) I think and believe that we can not hit the target by the end of the year. 

   我想并相信我们在年底前是无法完成指标的。

6. 当think出现在疑问句里时

(1) Do you really think that I didn’t notice the number? It was 2704. 

   你真的以为我连车号都没有注意吗？车号是2704。

7. 当think出现在含not just …but、just not …enough、not much、not quite等以not为核心的副词短语的句子里时

(1) I think Blanche didn’t just love him but worshiped the ground he walked on! 

   我认为，布兰奇不仅爱他，而且非常崇拜他。

(2) But I think that Elizabeth was not quite so certain of it as I. 

   但我认为，对于此事伊丽莎白未必比我有把握。

8. 当think出现在含can not help doing、ought not、need not、not at all等习语的句子里时

(1) I think I should have thought sometimes that you couldn’t help thinking of the past. 

   我想我本来应该想到你不禁会想起过去。

(2) I think you ought not to walk at night alone, Mrs. Moore. 

   穆尔夫人，我想你不该夜间一个人出去散步。

(3) “I think the angels are not at all in heaven.” Mr. Esmond said. 

   埃斯蒙德先生说，“我想天使根本不会死。”