The same change can be made to each word, name, or partial word below to create new words.

AA
ABE
PRESENT
INTIMATE

HINT:
The change involves the same two letters, in the same order.

Answer:

The letters ID can be inserted into each clue to give a new name or word:

AIDA
ABIDE
PRESIDENT
INTIMIDATE

Credit:  LA Times Crossword
Sylvia Bursztyn and Barry Tunick
ID REQUIRED