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foreshadowing
preparation; precautionary measures
後でその伏線に気づいた。
Later, I noticed that foreshadowing.
作者は物語の冒頭に伏線を張った。
The author laid foreshadowing at the beginning of the story.
その小説の伏線は、読者を驚かせるほど巧みだった。
The foreshadowing in that novel was so skillful it surprised readers.