1. What do the following three words have in common?

IT
MAID
CHANT

2. What do the following four words have in common?

DEB
PULP
PROF
PERM

HINTS:
1. Each word can be preceded by the same letters.
2. The same letters can be added to each word.

Answers:

1. Each word can be preceded by MER to form new words:

MERIT
MERMAID
MERCHANT

2. The letters IT can be added to the end of each word to form new words:

DEBIT
PULPIT
PROFIT
PERMIT

Credits:
#1:The Enigma
May, 2016
QT-OH

#2: Ed McCollum
LOSING IT