Answer:
The core of the plot is the life of Robinson on a desert island. This core of the narrative is framed on both sides by a description of Robinson's life before reaching the island and, likewise, upon returning to his native environment. This storyline plays the role of a kind of locomotive, flinging Robinson onto the island and then, after a quarter of a century, taking him from there. However, it carries a certain load in terms of the characteristics of the hero. It should be noted that the plot, eventful saturation of the small-volume pre-island part is much higher than the main narrative core, in which the event function partially passes into the internal aspect of experiencing, thinking, and reflecting the hero. A similar transition of the event load is noted by Robinson himself:
"I do not remember that I had in all that Time one Thought that so much as tended either to looking upwards toward God, or inwards towards a Reflection upon my own Ways: But a certain Stupidity of Soul, without Desire of Good, or Conscience of Evil, had entirely overwhelm'd me" (part 2).
Explanation: