The past participle of “do” is “done,” so it’s not “they have did what they promised not to do” but “they have done. . . .” But without a helping verb, the word is “did.” Nonstandard: “I done good on the test.” Standard: “I did well on the test.”
This is the ten-year anniversary of the Common Errors in English Usage calendar. To celebrate, we are bringing back some of our favorite interesting, funny, but sometimes merely silly entries through the years before going on hiatus in 2016.
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