Historical clue formulations

• Difficult effort — 2026-05-16
• Painful effort — 2022-10-13
• Labor — 2021-10-20
• Hard work — 2016-03-08
• Hard work — 2012-05-17
• Toil — 2007-04-22
• Moil and toil — 1994-10-02
• Drudgery — 1994-07-15