Voice

Hermione didn't quite know what to think of Harry for many different reasons.
First, there was his secretiveness and hesitance about basic things (his school, the 'special transfer program', where he lived).
Second, before Hogwarts, she was used to being seen as unusual, but Harry was a different kind of unusual. When the dementors had come inside the train, everyone had been a little worse for wear, but Harry had fainted and woken up asking about a woman screaming when there had been none.
 
Third, after the sorting ended and Dumbledore proceeded with the warnings, and then, "We have a transfer student joining the Third Years on a special program, everyone welcome Harith Potter, our newest Slytherin." There was the fact he neglected to mention he was Harry bloody Potter.
OR: Harry takes the Hogwarts Express and has a little surprise on his first day