1. What do the following words have in common?

SOB
DEIST
CHIEF
HENCE
DWINDLE

2. What do the following words have in common?

ESSAY
STALK
ENCHANT
RESTAURANT

HINT:
1. It has to do with the first letter of each word.

Answers:

1. Replacing the first letter of each word with a different letter gives five related words:

ROB
HEIST
THIEF
FENCE
SWINDLE

2. The last three, four, or five letters of each word describe a way of speaking:

esSAY
sTALK
enCHANT
restauRANT

Credit: EquinoxParty 42
National Puzzlers' League - Mar. 2006
Michael Constant
OH NO, NOT AGAIN