The following words can be changed into new ones, using different letters, but according to the same pattern. Can you figure out the pattern, the letters, and the new words?

LITTER
OREGON
TAMPED
RANGER
CROSS
ONSIDE (as a kick in football)

HINT: Add two letters to each word.

Answers:

Each word can be changed into a new one by adding one letter at the front of the word and one letter at the end:

GLITTERY
FOREGONE
STAMPEDE
ORANGERY
LACROSSE
CONSIDER

Credit:
NPR Weekend Edition Sunday Puzzle
December 25, 2005
Will Shortz