Riddle Me This/Riddle Me That

[MuGen]

Thats impossible...

A word of letters THREE - self explanatory.
ADD two - THREETWO or THREE + TWO?
Fewer it will be - THREE + TWO = FIVE having one fewer letter.

It's not a word that can be written three times over saying the same thing.

in response to the empty... answer

EDIT: Few is three letters and if you add two letters, Fewer it will be.....

The word is few...... thats pretty tricky.