What do the following words have in common?

APPLE
AUK
EARN
HEIR

HINT:
The same two letters can precede each word, with a spelling change, to form a new, rhyming word.

Answers:

CHAPEL
CHALK
CHURN
CHAIR

Note: Other words that also follow this pattern:

ACE (CHASE)
EASE (CHEESE)

Credit:
LA Times Crossword
October 18, 2015
Kathleen Faye O'Brien
CH-CHING!