 There is some derivation by means of prefixes and infixes, but it is no longer always productive, as those elements are often crystallized in words inherited from Old Khmer.Even in Old Khmer, the same affix could have multiple functions (for example, it could serve as a nominalizer in one word and as a causativizer in another).A common infix has the form or (or with other vowels), inserted after an initial consonant, especially to convert adjectives or verbs into nouns.