No! They heard! I was certain of it. They knew! Now it was they
who were playing a game with me. I was suffering more than I could
bear, from their smiles, and from that sound. Louder, louder, louder!
Suddenly I could bear it no longer. I pointed at the boards and cried,
“Yes! Yes, I killed him. Pull up the boards and you shall see! I killed
him. But why does his heart not stop beating?! Why does it not stop!?”

The author uses a lot of exclamation marks so emphasise that the main character is stressed and scared. This is an example of tone which defiantly develops, and leaves the story with a big note. This is a example of mood, because us as the readers we can see that the main character is getting more and more scared, because his sentences are either broken up into chunks, or they end in a exclamation mark.

The broken up in the text is showing us that he is stressed and scared; because when we get scared or stressed we tend to talk in short sharp sentences, unlike when we are talking calmly when we talk in nice care long sentences. This is an example of tone and mood because as the reader we can see that the narrator is getting stressed or scared, because he’s talking up in short sharp chunks, which leads to the book of the book to be more intense.