How does the author use foreshadowing in Their Eyes Were Watching God?

Consider the quote at the beginning of chapter one,

Ships at a distance have every man’s wish on board. For some they come in with the tide. For others they sail forever in the horizon, never out of sight, never landing until the watcher turns his eyes away in resignation, his dreams mocked to death by time. ch 1

This passage foreshadows Janie's journey in life. She dreams of true love, belonging, and a sense of independence: she is willing to explore to find these things.