Sentence structure? “Usually, I go surfing while the sun is coming up, but it was overcast and
foggy today.” ?

it's dangerous to surf during a foggy day

we need to see the document to answer the question

  this riddles' answer is library.

  the "leaves" are a reference to the books' pages that the library contains; the branches are a network of libraries that connect multiple libraries' collections, resources, and items in a system of a common database, integrating them; the branches' organization are a useful management tool for coordinating the multiple collections many libraries have.