Vietnamese morphology

Vietnamese, like many languages in Southeast Asia, is an analytic (and isolating) language. Vietnamese lacks morphological marking of case, gender, number, and tense (and, as a result, has no finite/nonfinite distinction).

Vietnamese is often erroneously considered to be a "monosyllabic" language. Vietnamese words may consist of one or more syllables. There is a tendency for words to have two syllables (disyllabic) with perhaps 80% of the lexicon being disyllabic. Some words have three or four syllables — many polysyllabic words are formed by reduplicative derivation.

Additionally, a Vietnamese word may consist of a single morpheme or more than one morpheme. Polymorphemic words are either compound words or words consisting of stems plus affixes or reduplicants.

Most Vietnamese morphemes consist of only one syllable. Polysyllabic morphemes tend to be borrowings from other languages. Examples follow:

Most words are created by either compounding or reduplicative derivation. Affixation is a relatively minor derivational process.

Older styles of Vietnamese writing wrote polysyllabic words with hyphens separating the syllables, as in cào-cào "grasshopper", sinh-vật-học "biology", or cà-phê "coffee". Spelling reform proposals have suggested writing these words without spaces (for example, the above would be càocào, sinhvậthọc, càphê). However, the prevailing practice (although considered careless to some) is to omit hyphens and write all polysyllabic words with a space between each syllable.

Reduplication, the process of creating a new word by repeating either a whole word or part of a word, is very productive in Vietnamese (as in other Austro-Asiatic languages), although not all reduplicative patterns remain fully productive.

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