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I'm here again... thanks for the sites indication!
but I have many doubts...
if both UN and IN is used to indicates NOT/OPPOSITE how can I know when I use IN or UN?
How can I know if the word has a prefix?
for e.g. Is "RE" a prefix of reduction ??
prefixes and suffixes 
Re: prefixes and suffixes 
Re: prefixes and suffixes 
Linear Mode
