A true fact, written in code. Each letter has been swapped for a different letter.

The rules

• The swap is the same everywhere: if Q stands for E once, every Q is an E.
• No letter stands for itself, and two code letters never stand for the same real letter.
• Two letters are filled in to get you started. Numbers and punctuation aren’t coded.

How to play

• Tap a letter in the puzzle, then tap a key to guess what it stands for. Every matching code letter fills in at once.
• A letter you’ve already used shows in orange where it clashes. ⌫ clears a guess.
• Decode the whole fact to earn today’s green check.

Tip: one-letter words are almost always A or I, and the most common three-letter word is THE.