The same two letters, in the same, consecutive order, will change each word below into a new one. What are the two letters and the three new words?

TIRE
SHOW
MEOW

HINT:
#1: The two letters are a word in their own right.
#2: The second letter is D.

Answer:

By inserting the letters AD into each word, you get three new words:

TIRADE
SHADOW
MEADOW

Credit: LA Times Crossword
June 12, 2015
Don Gagliardo and C.C. Burnikel
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