Thanks guys..I think it is what I was searching for!!! I will try it..Hopefully it works!

Thank you so much!
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Hello guys,
Unfortunately it was not what I meant. What I mean is: for example a create a Thread with the title "How to use Office" and then I write the content. After that, all the users can write something in the page where I wrote the content. Automatically, my post goes down, because the replies are more recent than my post. I want to avoid this JUST for some important contents that I write in some threads, not for every content. Is it possible?
For example in this thread, the posts are ordered by date..the new ones at the bottom. This is actually what I want..but not for every threads...just for some...
Thanks a lot