The same two letters, in the same, consecutive order, will change each word below into a new one.

BAN
CRY
PITY
BEAU
HOLY
STATE

Answers:
The letters are UR:

URBAN
CURRY
PURITY
BUREAU
HOURLY
STATURE 

Credit: New York Times Crossword
Lee Glickstein and Nancy Salomon 
August 7, 2005
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