| 1st and 2nd letters adjacent | 1st and 2nd letters (from end) adjacent | Starts with same letter |
| 2nd and 3rd letters adjacent | 2nd and 3rd letters (from end) adjacent | Ends with same letter |
| 3rd and 4th letters adjacent | 3rd and 4th letters (from end) adjacent | Starts and ends with same letter |
| Repeated n-grams | First letters in alphabetical sequence | Last letters in alphabetical sequence |