囚人

1. Origins, structure, and basic meaning

• Structure: 囚人 (しゅうじん) is a noun for a person deprived of liberty and held in custody under law or authority.
• Basic usage: 小説の囚人は手紙を書く makes a freedom-seeking prisoner the topic, while 囚人を作業場へ案内する makes the detained person the object escorted by a guard.

2. Common pitfalls and similar expressions

• Narrative subject and escorted detainee
  • 囚人は introduces the character’s own action, whereas 囚人を marks the person under a guard’s control. The noun does not include every accident victim trapped in a room.