Before the incident in the woods, how does the author build up tension to suggest something ominous might occur?

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To build up tension before the forest incident, the author can build a narration that imposes a totally unpredictable atmosphere and promotes a strong suspense in the reader. In this case, the author does not show any kind of foreshadowing, but only accumulates unpredictable, unthinkable and incalculable elements that make the reader understand that anything can happen at any time in history.

b. both have yearned to escape the environment they experienced as a child.