"This is my favorite theater."
Translation:Це мій улюблений театр.
You usually put a dash before "це," not after: Україна — це Європа (Ukraine is Europe). Here are some common usage rules http://www.ukrainianlanguage.org.uk/read/unit20/page20-2.htm
I keep spelling the last answer to this level "teatr" and it keeps saying that I am wrong. I even tried a Ukrainian font and spelled it in Ukrainian. Still wont move me on. This is very frustrating.