This is Part 1 of a two-week challenge. You’ll need to solve both parts before you send in your answer. So hold your answer for now.
These four words have a very interesting and unusual property in common. What is it?
You will need the second part of the two-week challenge before you can submit an answer to this puzzle. Tune in next Sunday or head to the Sunday Puzzle page on npr.org, Aug. 12, to hear the second clue for this challenge.