Historical clue formulations

• It may leave you speechless — 2024-02-03
• Timidity — 2023-05-22
• Introversion — 2017-04-02
• Cause of some blushing — 2008-05-16
• Social problem — 2004-10-13
• Reserve — 2003-12-28
• Wallflower's characteristic — 1997-05-20
• Diffidence — 1994-06-06