What do the following words have in common?

PARTY
DETER
SMILE
GENTLE
REVERE

HINT:
The same letter will change each word into a new one.

Answers:

Inserting the letter I into each clue will give new words:

PARTY - PARITY
DETER - DIETER
SMILE - SIMILE
GENTLE - GENTILE
REVERE - REVERIE

Credit: Will Shortz 
NPR Weekend Edition Sunday Puzzle 
June 2, 2013
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