What's the difference between:
"En fågel sitter på taket." and "Det sitter en fågel på taket." and "Det finns en fågel på taket." ?
Roughly the same difference as between the English sentences ”A bird is sitting on the roof.”, ”There is a bird sitting on the roof.” and ”There is a bird on the roof.”
Can it be both "There is sitting a bird on the roof" or "There is a bird sitting on the roof" ?
"There is sitting a bird on the roof" sounds very unnatural. The second sentence is good English, and it at least captures the sense of the Swedish sentence,
It is quite odd for me that birds are "sitting" on the roof. I would rather use "det finns" instead of "det sitter". Or maybe "det står" but sitter sounds unnatural to me.