In some languages, they are clearly defined; for example, in Chinese, there are three types of zhùcí (助詞; 'particles'): structural, aspectual, and modal.
However, Polynesian languages, which are almost devoid of inflection, use particles extensively to indicate mood, tense, and case.
[citation needed] According to this definition, particles are a separate part of speech and are distinct from other classes of function words, such as articles, prepositions, conjunctions and adverbs.
[citation needed] Languages vary widely in how much they use particles, some using them extensively and others more commonly using alternative devices such as prefixes/suffixes, inflection, auxiliary verbs and word order.
Particles are typically words that encode grammatical categories (such as negation, mood, tense, or case), clitics, fillers or (oral) discourse markers such as well, um, etc.
[1] Some commonly used particles in Afrikaans include: SySheisisnie1notmoegtirednie2PTCL.NEGSy is nie1 moeg nie2She is not tired PTCL.NEG'She is not tired'JyYoumoetmustonthourememberomCOMPtePTCL.INFeeteatJy moet onthou om te eetYou must remember COMP PTCL.INF eat'You must remember to eat'PeterPetersePTCL.GENboekbookPeter se boekPeter PTCL.GEN book'Peter's book'dietheboekbookvanPTCL.GENPeterPeterdie boek van Peterthe book PTCL.GEN Peter'Peter's book'soPTCL.CMPRgrootbigsoosPTCL.CMPR'nahuishouseso groot soos 'n huisPTCL.CMPR big PTCL.CMPR a house'as big as a house'Particles in Arabic can take the form of a single root letter before a given word, like "-و" ('and'), "-ف" ('so') and "-ل" ('to').
[3] The Concise Oxford Companion to the English Language defines a particle as a "word that does not change its form through inflection and does not fit easily into the established system of parts of speech".
[4] A German modal particle serves no necessary syntactical function, but expresses the speaker's attitude towards the utterance.
"[5] These particles are common in speech but rarely found in written language, except that which has a spoken quality (such as online messaging).
Polynesian languages are almost devoid of inflection, and use particles extensively to indicate mood, tense, and case.
In Māori for example, the versatile particle e can signal the imperative mood, the vocative case, the future tense, or the subject of a sentence formed with most passive verbs.
[23] In Russian, particles sometimes play an important role making an additional nuance for a meaning of a phrase or of a whole sentence.