"Where is the hospital?"
And also very important are the tones:
哪 nǎ - where?
Third tone, your voice goes slightly down but then in the end up, just like a question in English (Whěre?).
那 nà - there!
Fourth tone, your voice goes from high up straight down, the tone comes quite close to how you would say it in Englisch: Thère! ;o)