这个不一定,时态在广泛的英语世界中是非常灵活的.但是在中学阶段比较狭隘.I found that my book was lost.(指当时---我发现书丢了.）总结,一般情况,I found后面跟过去相关的时态（一般过去时,过去将来时,过去完成时等等）.think that后面的时态更多,I think that he is coming soon.（进行时表将来）,I think that he was crazy yesterday.（过去时）,I think that he has made it.(现在完成时）,其实还有很多很多种可能.