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 with perhaps 80% of the lexicon being disyllabic. Some words have three or four syllables — many polysyllabic words are formed by reduplicativederivation. 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. However, the prevailing practice is to omit hyphens and write all polysyllabic words with a space between each syllable.
Word-formation
Reduplication
, the process of creating a new word by repeating either a whole word or part of a word, is very productive in Vietnamese, although not all reduplicative patterns remain fully productive.
Function and semantics
Its effect is to sometimes either increase or decrease the intensity of the adjective, and is often used as a literary device in poetry and other compositions, as well as in everyday speech. Examples of reduplication increasing intensity:
A type of assimilation known as tonal harmony is involved in Vietnamese reduplication. The six tones are categorized into two registers: The tones of all reduplicated words are always within the same tonal register. For example, nhỏ "small" with the hỏi tone when reduplicated appears as nho nhỏ "smallish" with a ngang-toned reduplicant — both syllables are in the upper tonal register. Vietnamese has several different types of reduplicative patterns including both total, partial, initial, final, rhyming, and alliterative patterns involving only reduplicated material or both reduplicated material and affixation. Reduplicant position. The resulting reduplicants can be either initial or final. Total reduplication involves copying the entire word base:
Partial reduplication involves copying only certain segments of the word base. Partial reduplication typically involves the affixation of non-reduplicated segments.
Affixation
Vietnamese has very limited affixation. Only prefixation and suffixation are attested. A few affixes are used along with reduplication. Many affixes are derived from Sino-Vietnamese vocabulary and learned part of the lexicon. Some examples follow.
Ablaut
Vietnamese has the following tonal alternations which are used grammatically: Vietnamese also has other instances of alternations, such as consonant mutations and vowel ablaut. Different regional varieties of Vietnamese may have different types of alternations.
