1. The same three letters, in the same order, will complete the four-letter words below.

_ _ _ D
_ _ _ E
_ _ _ K
_ _ _ M
_ _ _ N

2. The same two letters, in the same, consecutive order, will change the three words below into new ones.

CAR
CAVE
COMB

Answers:

1. The letters are WOR:

WORD
WORE
WORK
WORM
WORN

2. The letters AT can be added at the end of each word to create a new one:

CARAT
CAVEAT
COMBAT

Credit #2:
NY Times Crossword
January 24, 2018
Kathy Wienberg