English has more than a hundred common prefixes and suffixes -able, -ness, -ment, pre-, dis-, anti-, and so on and with these it can form and reform words with afacility that yet again sets it apart from other languages. For example, we can take theFrench word[12] It must be exasperating for foreigners to have to learn that a thing unseen is notunvisible, but invisible, while something that cannot be reversed is not inreversible, butirreversible and that a thing not possible is not nonpossible or antipossible but impossible.Furthermore, they must learn not to make the elementary mistake of assuming thatbecause a word contains a negative suffix or prefix it is necessary a negative word. In-,for instance, almost always implies negation but not with invaluable, while –less isequally negative, as a rule, but not with priceless.