The same two letters, in the same, consecutive order, can be added to each of the words below to make new words. The letters may be added at any point in the clue words, but they remain in consecutive order. What are the letters, and what are the new words?

AT
IN
ME
UP
BAN
BEAN
ACHES

Answers:

The letters are CO:

COAT
COIN
COME
COUP
BACON
BEACON
COACHES

Credit:
LA Times Crossword
August 21, 2016
Gail Grabowski 
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