What do the following words have in common?

1. FUR
2. LABOR
3. VICAR
4. IMP
5. COP
6. SPUR

HINT:
All six words can be followed by the same four letters, in the same order, to form new words.

Answers:

Each word can be followed by IOUS to form new words:

1. FURIOUS
2. LABORIOUS
3. VICARIOUS
4. IMPIOUS
5. COPIOUS
6. SPURIOUS 

Credit: GAMES Magazine
September, 2010
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