"This is a very big movie theater."
Translation:Це дуже великий кінотеатр.
'movie-theatre' is very unlikely, certainly in British English: more natural would be 'cinema'. 'Movie-theatre' looks like a from inspired by the Ukrainian word......
Movie theater, movie theatre and cinema are all accepted. I do agree that "cinema" is as common as "movie theater" if not more; so I gave it "bigger priority" to be shown in exercises :) Thank you.