I left out the following sentences. Thank you. I also included the sentences you told me to divide.

1) How was it possible that they could not hear it? In fact, the police officers must have heard it, the narrator decided. And they must have suspected him of a crime all along.
2)Their calm manner and idle chatter were part of a ruse to mock him. Unable to brook their counterfeit behaviour any longer, unable to endure the sound any longer, the narrator confessed to his crime.
3) On that particular night, unlike the preceding seven nights, the narrator opened the door with greater caution. However, he made a noise when he was going to open the lantern and the old man immediately sprang up in bed and got scared.
4) The old man’s eye was open, which made the narrator angry and froze his blood. The narrator kept still, he didn’t move a muscle and said nothing.

3 - comma after "lantern"

All else is OK.

1) To answer the question, "How was it possible that they could not hear it?", we can examine the information provided. The narrator is questioning how the police officers did not hear something, suggesting that they should have heard it. The narrator further concludes that the police officers must have heard it and suspected him of a crime all along.

To arrive at this answer, we can analyze the given sentences. The narrator's deduction suggests that the police officers had some reason to suspect him. This is supported by the fact that the narrator assumes the police officers must have heard something, indicating that they were present and paying attention. Therefore, the answer to the question is that the narrator believes the police officers must have heard the noise and suspected him of a crime.

2) The given sentences describe the narrator's feelings towards the calm manner and idle chatter of the police officers. The narrator perceives their behavior as a ruse to mock him. Feeling unable to tolerate their counterfeit behavior any longer and unable to endure the sound, the narrator confesses to his crime.

To understand the situation, the sentences provide context about the narrator's emotions and his decision to confess. The narrator perceives the calmness and idle chatter as insincere, leading him to believe that they are mocking him. This, along with his inability to bear the noise any longer, drives him to confess. Therefore, the answer to this part is that the narrator confesses to his crime due to his perception of the police officers' behavior and his inability to bear the sound.

3) The provided sentences depict the events leading up to the old man's reaction. The narrator opens the door with greater caution on that particular night, but makes a noise while opening the lantern. The old man immediately springs up in bed, startled and scared.

To find the answer, we can examine the information given. The narrator takes extra care when opening the door, but unintentionally makes a noise while opening the lantern. This sudden noise startles the old man, causing him to wake up in bed and become scared. Therefore, the answer is that the old man reacts out of fear and surprise because of the noise made by the narrator.

4) The given sentences describe the narrator's reaction to the old man's open eye. The narrator becomes angry and feels his blood freeze. He decides to keep still, not moving a muscle, and says nothing.

To understand the situation, we can analyze the provided sentences. The narrator's anger and freezing blood indicate a strong emotional response to the open eye of the old man. In response to these feelings, the narrator elects to remain motionless and silent. Therefore, the answer is that the narrator becomes angry, feels his blood freeze, and chooses to stay still and quiet.