I don’t know how to phrase the search query for this, so if the answer is hidden in the meltdown archives I apologise.
So, once upon a time I read a sentence with innumerable
consecutive "had"s and, now, I have no idea what the sentence was, or the maximum number of hads.
Calling all English teachers! Help! Else, I shall go nucking futs.
I used to give this as a sort of bonus question to my students (they had to punctuate it correctly). Surprisingly, every time I did, someone got it correct.