1. What do the following words have in common?

ONE
OWN
OUGHT

2. The same change can be made to each of the words below to create new ones.

STOCKS
POCKET
SNORED
GROVEL
OBJECT


Answers:

1. Each word can be preceded by DR to make a new word:

DRONE
DROWN
DROUGHT 

2. Changing the "O" in each word to "A" gives new words:

STACKS
PACKET
SNARED
GRAVEL
ABJECT