This extract is the start of the Quidditch game in chapter 11, page 136 in the English edition, starting from : "Wood cleared his throat for silence ..." and ending with "Gryffindor score!" The Greek follows the convention of beginning direct, quoted speech with a capital letter, not using quotation marks. The first 4 words are the title! (Harry Potter : Quidditch!). You may prefer to put paragraphs where the individual speakers change.