Need help!! Please!!

I am SO very sorry to do a double post, but I cannot find the previous thread. There was a topic about what the difference between "theatre" and "theater" is. I need to know it for a speech that I am writing...I don't know which to use!! Please help!! If you can find me the other topic, or just answer this question here I would greatly appreciate it!

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I remember from my drama class that THEATER was the building while THEATRE was the actual act of performing. hope this helps.

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Not true.

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