The following two sets of words have something in common.

ORES

ITCH

AIRWAY

RANGE

FIR

HONE

BUR

AGAIN

HINT:

The words in both sets can be changed by adding the same two letters.

Answers:

The letters ST can be added to the beginning of the first set of words and to the end of the second set to create new words.

STORES

STITCH

STAIRWAY

STRANGE

FIRST

HONEST

BURST

AGAINST