In her third year she had to keep her time turner hidden from everyone including Harry and Ron. In fourth year she kept who she was going to the ball with a secret and she never told Harry or Ron that she kissed Victor Krum.
Hermione Granger can learn in every way (tactile, seeing, and hearing) so she is great at absorbing knowledge. She also reads many books and takes notes in class. She has a good memory! No one can know 'everything'
Hermione practises what spells she is said to practise. She reads her notes to remember what she learned. She also thinks logically although she is wrong at some points. She is also a very good listener and is able to interpret things with great detail.
However, Hermione doesn't "know everything." She didn't know about Horcruxes, who RAB was, the prophecy about the Chosen One, what a Mudblood was, who Nicolas Flamel was, how to play Wizard Chess, and many more things.
It was probably that she had a crush on Professor Gilderoy Lockhart. Also, she shared a secret with Ron and Harry that they were brewing Polyjuice Potion in the girl's bathroom against the rules.
When Ron and Harry are trying to destroy the locket (a horcrux) Ron opened the locket, and an image of Harry and Hermione appeared with Hermione telling Ron how much better Harry Potter is, and when you could have Harry Potter, why would anyone want Ron Weasly. Then her and Harry start kissing, and Ron stabs the horcrux, killing it.
(Sadly, this answer has nothing to do with the question.)
Hermione's secret in Harry Potter 3 is the fact that she is taking extra classes using the Time-Turner.
Hermione Granger
finite incantartem
The movie chamber of secrets
If you mean the invisibility cloak then Harry Potter, Ron Weasey and Hermione Granger use it at various points.
Harry potter and the chamber of secrets , is the second book of the series.
No you can only play as Harry in Harry Potter and the Chamber of Secrets. You can play as Hermione in Prisoner of Azkaban.
No, Harry never had a crush on Hermione.
Hermione Granger
Ron Weasley and Hermione Granger.
finite incantartem
In Harry Potter and the Chamber of Secrets, one sub-adventure is when Hermione, Ron and Harry try to get Crabbe's and Goyle's hair for the polyjuice potion.
Dumbledore, Ron, Hermione, Ginny, and the Gryffindor House for the most part.
The movie chamber of secrets
Yes. Ron and Hermione go down to the Chamber to get some Basilisk fangs which can be used to destroy Horcruxes.
Harry potter and the chamber of secrets , is the second book of the series.
If you mean the invisibility cloak then Harry Potter, Ron Weasey and Hermione Granger use it at various points.
ron and hermione or if you mean the person in the book in the book it is tom riddle