Historical clue formulations

• Participate in drudgery — 2026-08-01
• Drudgery, in older usage — 2020-02-10
• Be in continuous agitation — 2015-09-12
• Turbulence — 2013-04-07
• Work hard — 2012-04-05
• Work hard — 2007-09-06
• Do drudgery — 2004-03-14
• Drudgery — 2003-06-18
• Churn — 2001-07-31
• Drudge — 2000-05-20
• Drudge — 1999-08-19
• Work hard — 1997-12-10
• Drudge — 1995-04-29