Finnish (suomi, or suomen kieli [ˈsuomen ˈkieli]) is a Finnic language spoken by the majority of the population in Finland and by ethnic Finns outside Finland. It is one of the two official languages of Finland and an official minority language in Sweden. In Sweden, both standard Finnish and Meänkieli, a Finnish dialect, are spoken. The Kven language, a dialect of Finnish, is spoken in Northern Norway by a minority group of Finnish descent.

Linguistics

Classification
Finnish's full classification (using an agnostic approach that assumes all branches are distinct, since Finno-Urgic having been challenged and abandoned by Ethnologue) is as follows:
Uralic (Proto-Uralic) > Finnic (Proto-Finnic) > Finnish
Phonology and Phonotactics
Standard Finnish has 8 vowels and 18 diphthongs. Vowels are contrasted based on length, with both long and short vowels existing. These contrasts occur in both stressed and unstressed syllables, though long vowels tend to be more common in short syllables. There is almost no allophony between among the Finnish vowels.
Finnish has 13 consonant sounds, and, like the vowels, these too can be short or long (gemination), with these being phonemic. Independent consonant clusters are not allowed in native words, except for a small set of two-consonant syllable codas, e.g. 'rs' in karsta. However, because of a number of recently adopted loanwords using them, e.g. strutsi from Swedish struts, meaning "ostrich", Finnish speakers can pronounce them, even if it is somewhat awkward.
The main stress is always on the first syllable. Stress does not cause any measurable modifications in vowel quality (very much unlike English). However, stress is not strong and words appear evenly stressed. In some cases, stress is so weak that the highest points of volume, pitch and other indicators of "articulation intensity" are not on the first syllable, although native speakers recognize the first syllable as a stressed syllable.
Finnish has several morphophonological processes that require modification of the forms of words for daily speech. The most important processes are vowel harmony and consonant gradation.
Vowel harmony is a redundancy feature, which means that the feature [±back] is uniform within a word, and so it is necessary to interpret it only once for a given word. It is meaning-distinguishing in the initial syllable, and suffixes follow; so, if the listener hears [±back] in any part of the word, they can derive [±back] for the initial syllable. For example, from the stem tuote ("product") one derives tuotteeseensa ("into his product"), where the final vowel becomes the back vowel 'a' (rather than the front vowel 'ä') because the initial syllable contains the back vowels 'uo'. This is especially notable because vowels 'a' and 'ä' are different, meaning-distinguishing phonemes, not interchangeable or allophonic. Finnish front vowels are not umlauts.
Consonant gradation is a partly nonproductive lenition process for P, T and K in inherited vocabulary, with the oblique stem "weakened" from the nominative stem, or vice versa. For example, tarkka "precise" has the oblique stem tarka-, as in tarkan "of the precise". There is also another gradation pattern, which is older, and causes simple elision of T and K in suffixes. However, it is very common since it is found in the partitive case marker: if V is a single vowel, V+ta → Va, e.g. *tarkka+ta → tarkkaa.
Finnish syllable structure can be classified as (C)V(S)(C) where (S) stands for 'segment', either a consonant or a phoneme. There are some rare syllables that break these general rules, but the basic syllable type given above constitute well over 90% of the words.
Grammar
Finnish is an agglutinative language. Finnish word order is fairly free, though a general tendency towards subject-verb-object does exist. However, this is often overridden by the fact that the topic of the conversation comes first (if talking about a man that was bitten by a dog, the word for man would come first).
Neither Finnish nouns nor pronouns decline for gender. There is also no article in the language. However, Finnish does distinguish 15 (16 in some dialects) noun cases. There are four grammatical cases (nominative, genitive, accusative and partitive), six locative cases (inessive, elative, illative, adessive, ablative, allative), two (three in some dialects) essive cases (essive and translative) and three 'marginal cases' (instructive, abessive and comitative).
Finnish has 7 pronouns, distinguishing three persons and two numbers (singular and plural), but no gender distinction in the third person. The seventh pronoun is a formal 2nd person. While the first and second person pronouns are generally dropped in Standard Finnish, they are common in colloquial speech; third person is required in both standard and colloquial Finnish. The third person pronouns, hän and he are often replaced with se and ne (singular and plural, respectively) in colloquial speech.
Finnish adjectives share the inflection paradigms of Finnish nouns and must agree with the noun in both number and case. Adverbs are generally formed by adding the suffix -sti to the inflecting form of the corresponding adjectives. Outside of this derivational process, they are not inflected.
Being a case rich language, Finnish has few post- or prepositions. However, what few it has tend to be postpositions. When the postposition governs a noun, the noun takes the genitive case. Likewise, a postposition can take a possessive suffix to express persons. Prepositions tend to take nouns in the partitive case.
Finnish has six conjugation classes; even though each class takes the same personal endings, the stems take different suffixes and change slightly when the verb is conjugated. Finnish has very few irregular verbs, and even some of those are irregular only in certain persons, moods, tenses, etc.
Finnish verbs can conjugate for four tenses: non-past, historically called the present, which can express the present or the future; preterite, historically called the imperfect, which covers English past simple and past continuous; perfect, which corresponds to the English present perfect; plusperfect, which corresponds to the English past perfect.
Finnish verbs can also conjugate for two voices, the active and the passive. The Finnish passive is unipersonal, that is, it only appears in one form regardless of who is understood to be performing the action. In that respect, it could be described as a "fourth person", since there is no (standard) way of connecting the action performed with a particular agent.
Finnish verbs conjugate for five different moods. These are the indicative, the conditional, the imperative (split into several types), the optative and the potential. A sixth mood, the eventitive, is no longer used in Finnish, but is the mood used in the Finnish epic poem Kalevala.
Finnish infinitives can come in four, sometimes analyzed as five, different groups. The first one is the citation form of the infinitive and corresponds to the English 'to X' infinitive use. The second infinitive is used to express aspects of actions relating to the time when an action takes place or the manner in which an action happens. In equivalent English phrases these time aspects can often be expressed using 'when', 'while' or 'whilst' and the manner aspects using the word 'by' or else the gerund, which is formed by adding "ing" to English verb to express manner. The third infinitive corresponds to the English gerund while the fourth and the fifth, both of which are rare in Finnish today, mark obligation and 'just about to...' respectively.
Miscellany

• Finnish, with 15/16 cases, has more cases than its ancestor Proto-Uralic, which is typically reconstructed with six; so, unlike most Indo-European languages, Finnish gained cases over time.
  
• The exessive case is the essive case found only in some dialects
  
• Finnish has borrowed extensively, with some linguists positing that only 300 Proto-Uralic words can be found in Finnish; however, due to the radical differences between Finnish and its Indo-European neighbors, borrowings quickly get nativized.
  
• Some Finnish loan words do not seem to have come from Indo-European languages or have cognates in other Uralic languages. It is possible that these are borrowings from whatever languages were spoken in Europe before the spread of Indo-European languages.
  
• Finnish orthography is highly phonemic, and, barring distinctions between colloquial and standard forms, one can often "write as you read, read as you write".
  
• The language's orthography is often easily-recognizable because of its lack of b, c, f, q, w, x, z and å.
  

Samples

Spoken sample:
https://www.youtube.com/watch?v=hFCixLn9qRw (Lullaby)
https://www.youtube.com/watch?v=ejIdIKidqcc (folk song)
https://www.youtube.com/watch?v=SCEw4uH2a8I&list=PLL92dfFL9ZdJBbTpg-h9AMnZfxNlHwrbh (Playlist of songs popular in Finland currently)
https://www.youtube.com/watch?v=7vYH1JH73pw (Finnish newscast on Bitcoin)
Written sample:
Vaka vanha Väinämöinen itse tuon sanoiksi virkki: "Näistäpä toki tulisi kalanluinen kanteloinen, kun oisi osoajata, soiton luisen laatijata." Kun ei toista tullutkana, ei ollut osoajata, soiton luisen laatijata, vaka vanha Väinämöinen itse loihe laatijaksi, tekijäksi teentelihe.
(Verses 221-232 of song 40 of the Kalevala) Audio here
Kaikki ihmiset syntyvät vapaina ja tasavertaisina arvoltaan ja oikeuksiltaan. Heille on annettu järki ja omatunto, ja heidän on toimittava toisiaan kohtaan veljeyden hengessä.
(Article 1 of the Universal Declaration of Human Rights)

Sources

Further Reading

• Wikipedia page on Finnish, and related links
  
• Finnish Sound Structure: Phonetics, phonology, phonotactics and prosody (Suomi, Toivan and Ylitalo 2008)
  

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