"Where is this gym?"
Translation:Де цей фітнес-зал?
Because then we would have to add "знаходиться, знаходяться, знаходишся, знаходжуся, знаходився, ......" to almost every sentence with "to be" :')
It's correct, but doesn't have a direct translation to English. Let's translate "to be" as just "to be".
If you know this verb, your Ukrainian level is already quite high :)