Puis-je répondre en anglais? Si tu ne comprends pas, dites-moi et je répondrai encore une fois en français.

Holmes and Watson do not go into Helen’s room. They go into the sister’s former room where Helen is now sleeping and they discover some strange things. First, they notice that there is a bell rope on the ceiling that is supposed to be used for calling a butler. However, when they pull the rope, they realize that it is fake. It is not attached to anything and does not ring any bell. Next, they notice a ventilator in the room. Holmes decides he and Watson must spend the night in Helen’s room because they suspect her stepfather is planning some evil deed. So, Holmes and Watson then spend the night in the room where Helen is now sleeping (her sister’s former room). Helen has not been sleeping in her original room because her stepfather has told her he needs to make some repairs, which is a ploy to get her out of her room and into her sister’s former room. At the end of the story, the reader learns that the rope is for the poisonous snake to crawl down through the ventilator, bite the girls and kill them. Holmes suspects this and when he hears the snake hiss, jumps up, hits it, it flees up the rope through the ventilator and bites the stepfather, killing him. Elementary, my dear Watson!

Ooops........sorry.........two teachers must have been working on the answer to this at the same time.

When Holmes and Watson go to the Stoke Moran Manor House and see Helen's room, the strange things they see there have to do with the "improvements" that were made about three years before.

The first strange thing is the bell rope.  Helen's sister did not really need it at all, so why was it put it?  More importantly, why is it not really connected to a bell?  Instead, it is just connected to a hook.

The hook is in a ventilating grille, which is the other strange thing.  Why does the ventilation duct connect to another room when it would be so much easier to connect with the outside.

Of course, both of these things have been done so that Dr. Roylott could use his snake to kill whoever was in that room.