Here Rainsford is trying not to lose his mind. He knows that if he starts freaking out he will most likely make a mistake and get caught by Zaroff. This creates suspense in the storey because we want to see if Rainsford can keep calm, or if he breaks.
Here Rainsford has beaten Zaroff att his game. Rainsford climbs up to Zaroff's bedroom and surprises him. This is important to the story because it is the climax of the story. Here we find out if Rainsford will live or die.
Here Rainsford has jumped off a cliff trying to run away from Zaroff. This was very This adds suspense to the story because we do not know if he will survive the fall or if he will die.