Historical clue formulations

• At ___ (befuddled) — 2021-09-25
• Thrown for ___ — 2014-05-20
• At ___ (stumped) — 2012-12-10
• Throw for ___ — 2012-11-11
• At ___ for words — 2010-06-29
• At ___ for words — 2010-04-25
• At ___ for words — 2007-04-03
• Throw for ___ — 2004-02-06
• Perplexed, after "at" — 2002-08-22
• Thrown for ___ — 2002-05-07
• At ___ for words — 2002-04-02
• "What ___!" (words of regret) — 2001-03-25
• At ___ for words — 1999-04-19
• Perplexed, after "at" — 1999-02-13
• At ___ (stumped) — 1998-07-11
• At___for words — 1996-03-11
• Throw for___ — 1996-02-25
• Throw for _____ — 1994-04-29