"Is she big?"
Why do you not use "to" here? I thought if you are in third person then you must be specific, so don't you need a "to" or "ona" before or after the "je" ?
From veliká, we know that the subject is feminine singular. So alternatives using ona also are accepted, but the pronoun is not required.
I will add, because your other questions also showed this confusion, that you often do not have to be specific. Natural languages are usually potentially ambiguous and it is often the context that resolves this ambiguity. That is true for English as well.
That is not correct at all. Are you sure you are a native Czech? The course authors are.
Dear Vlada. Thank you for your message. Yes, I am native Czech. In that case, I do not know what to do with it.
Best to check the facts in a dictionary or a grammar handbook before complaining.
Dear Vlad. I do not complain. I only joined the discussion. Perhaps it would not be wrong to ensure that the program accepts both options. Both velký and veliký. What do you think about it?
Both velká and veliká are accepted for this sentence, and often are for others. if you come across one that doesn't accept both, you can Report your answer. It's possible that an alternative translation is just missing here and there.