Week 0:
The set of all words beginning with a letter between Q and Z inclusive: NONE
The set of all words whose letters have a combined point value of 15 or higher in English-language Scrabble (examples: JOKE, ZZZ): ONE
The set of all words where exactly two of the letters are A, E, I, O, U, or Y: TWO
The set of all words containing a double letter (examples: EGG, BOOT, LLAMA; counterexamples: FIFE, NANA): ALL
Week 1:
[Daniel Levitin] The set of all words of length greater than 10: NONE
[Inge S. Kraft] The set of all words that appear as distinct words in William Shakespeare's Hamlet (as opposed to as substrings of words), according to www.rhymezone.com/shakespeare (example: BORROWER, counterexample: ROWER): ONE
Week 2:
[Jason Boomer] The set of words with length of 8 or more: ONE
[Jessica Timmerman] The set {BALLOON, BEEPED, BOOKING, BOOMING, BULLFROG, CHICKEN, FEED, FEELING, FOOD, GULL}: NONE
[John Bulten] The set of all words with second-to-last letter between L and S inclusive: ONE
[Kenneth Wilson] The set of all words that appear as distinct words in William Shakespeare's Antony and Cleopatra (as opposed to as substrings of words), according to www.rhymezone.com/shakespeare (example: BRANCHLESS, counterexample: RANCH): NONE
[Kevin Orfield] The set of all words containing a double vowel (AA, EE, II, OO, UU, YY): NONE
[Kevin Orfield] The set of all words containing a double vowel (AA, EE, II, OO, UU, YY): NONE
[Kyle Nils] The set of all words beginning with a vowel (A, E, I, O, U, Y): NONE
[Sam Levitin] The set of all words of length 6 through 10: ALL
[Sam Levitin] The set of all words of length 6 through 10: ALL
[Arkayde] [private guess of a set of 3 words]: NONE
[Inge S. Kraft] The set of all words in which either the first or the second letter appears in the string HE WEARS MANY HATS: NONE
[John and Izak Bulten] The set of all words containing a double letter between NN and ZZ inclusive: TWO
[Kenneth Wilson] The set of all 6- and 7-letter words that contain the letter O at least once: ONE
[Kevin Orfield] The set of all words ending with a double letter: NONE
[Kyle Nils] The set of all words beginning with a letter between J and P inclusive*: NONE
[Sam Levitin] The set of all words with 3 or more consecutive consonants (consonants being defined as all letters except A, E, I, O, U, and Y): ONE
*Kyle didn't clarify in time whether this included J and P or not; I went with inclusive because it matched the week 0 clue. Better to give information that wasn't intended to be asked for than no information.
