Japanese Grammar
Certain aspects of Japanese grammar are highly controversial. Japanese grammar can be characterized by the following prominent features:The basic sentence structure of a Japanese sentence is topic-comment. For example, consider the sentence "kochira wa, Sanga san desu". Kochira is the topic of the sentence, indicated by the particle wa; this means "as for this person". The verb is desu ("be"). As a phrase, Sanga san desu is the comment. This sentence loosely translates to "As for this person, (it) is Mr Sanger". So Japanese, like Korean and somewhat like Chinese, is often called a topic-prominent language, which means it marks topic separately from subject, and the two do not always coincide.
Japanese nouns in general have neither number nor gender. Thus hon (book) can be used for the singular or plural. However, in the case of a small number of native words (of proto-Japanese rather than Chinese origin) plurality may be indicated by reduplication. For example, hito means "person" while hitobito means "people"; ware is a form of "I" while wareware means "we" (although the kun'yomi "ware" may also be of Chinese origin, just more ancient than the Chinese on'yomi readings). Sometimes suffixes may also indicate plurality. Examples include the suffixes -tachi and -ra: watashi, a form of "I", becomes watashitachi, meaning "we", and kare (him) becomes karera (them).
With some exceptions Japanese is SOV (with the verb at the end of the sentence.) It also has an unmarked phrase order of Time Manner Place (the reverse of English order).
Verbs are conjugated to show tenses, of which there are two: past and present (also called non-past tense, since the same form is used for the present and the future). The present tense in Japanese serves the function of the simple present and the future tense, while the past tense (or perfect tense) in Japanese serves the function of the simple past tense. The distinction is between actions which are completed (perfect) or are not yet completed (imperfect). The present perfect, present continuous, present perfect continuous, future perfect, future continuous, and future perfect continuous are usually expressed as a gerund (-te form) plus the auxiliary form imasu/iru. Similarly, the past perfect, past continuous, and past perfect continuous are usually expressed with the gerund plus the past tense of imasu/iru. For some verbs, that represent an ongoing process, the -te iru form regularly indicates a continuous (or progressive) tense. For others, that represent a change of state, the -te iru form regularly indicates a perfect tense. For example, kite imasu regularly means "I have come", and not "I am coming", but tabete imasu regularly means "I am eating", and not "I have eaten". Note that in this form the initial i of imasu/iru is often not voiced, especially in casual speech and the speech of young people. The exact meaning is determined from the context, as Japanese tenses do not always map one-to-one to English tenses. In addition, Japanese verbs are also conjugated to show various moods.
There are three types of words that correspond to adjectives in English: stative verbs (also called i-adjectives), copular nouns (na-adjectives), and the limited set of true adjectives in Japanese. Both copular nouns and stative verbs may predicate sentences, and both inflect, though they do not show the full range of conjugation found in other verbs. There is a regular way to turn the stative verbs into adverbs. The true adjectives are limited to modifying nouns.
The grammatical function of nouns is indicated by postpositions. These include possession (no), subject (ga), direct object (o), indirect object (ni) and others. The topic is also marked by a postposed particle (wa). These particles play an extremely important function in Japanese.
Japanese has many ways to express different levels of politeness, including a different conjugation for verbs, special verbs and pronouns, verbs indicating relative status, use of different nouns, etc., as shown above.
The verb desu/da is the copula verb, though it doesn't play all the roles of the English "to be" and often takes on other roles. In the sentences above, it has played the copulative function of equality, that is: A = B. However a separate function of "to be" is to indicate existence, for which the verbs arimasu/aru and imasu/iru are used for inanimate and animate things respectively.
Strictly speaking, desu is a contraction of -de, the particle indicating subject complement, (see copula) and su, an elision of gozaimasu (a polite copula). So an alternative, more accurate (though seldom seen) parsing of Kochira-wa, Sumisu-san desu is Kochira-wa, Sumisu-san-de su:
Kochira-wa This person, subject
Sumisu-san-de Mr Smith, subject complement
su (=gozaimasu) is, (animate)
The verb "to do" (suru, polite form shimasu) is often used to make verbs from nouns of action and state (aisuru "to love", benkyosuru "to study", etc.). Japanese also employs regular compounding of verbs (e. g. tobidasu "to fly out, to flee" from tobu "to fly, to jump" + dasu "to go out").
There are many derivative forms of words that may turn one part of speech into another. Nouns can be made into verbs, adjectives into nouns, gerunds, and other forms, and so on. Verbs, in addition to other derived forms, have one (the -tai form) which is an adjective meaning "want(ing) to do X"; e.g., tabetai desu means "I want to eat".
Japanese has a lot of pronouns for use in different occasions, and different pronouns for men and women, younger or older, etc. These pronouns are not used all the time, but often elided when the reference has been established and is obvious from context. Japanese is therefore called a pro-drop language. For example, instead of saying "Watashi wa byoki desu" ("I am sick"), one would simply say "Byoki desu" ("Am sick"). A single verb can often constitute a complete sentence.
