I answered: Please take me to the colosseum. It was marked wrong. Instead, the correct solutions came up as:
• Please take me to Colosseum.
• Take me to the Coliseum, please.
I am going to report that my answer should have been accepted but, if anyone can give a good reason why it shouldn't be, please let me know.
This is not just any stadio but the Colosseum in Rome, which is not a word like stadio describing the type of building but the actual name of the place. In English "take me to the church" vs "take me to St. Peter's" where the article is dropped. Perhaps English is the odd one for still using an article with Colosseum.
I read a little bit into the subjuctive present tense, and (someone Italian correct me if i'm wrong) it seems that some verb forms conjugate the same way in the imperative and subjunctive. Portare as an "are" verb in the subjuctive conjugates into "porti" for me, you singular, and he/she/it. Coincidentally the same as how it conjugates under imperative for you singular. What makes this considered a subjuctive is that the subjuctive is sometimes used as a way to give a somewhat polite demand or request as via subjuctive you're saying something along the lines of "you may take me to the colosseum". I think.