puzzle remains

Examples (10)

• The cause of the fire remains a puzzle to investigators.
• Despite years of research, the puzzle remains unsolved.
• How they managed to escape remains a complete puzzle.
• The puzzle remains of why the ancient civilization disappeared so suddenly.
• It remains a puzzle why she decided to leave without saying anything.
• The puzzle remains for scientists studying these deep-sea creatures.
• Even with new evidence, the puzzle remains as complex as ever.
• His sudden disappearance remains a puzzle that haunts the small town.
• The central puzzle remains: who was the mysterious benefactor?
• For many historians, the puzzle remains regarding the king's true intentions.