Those who are learning Japanese must have known that Japanese grammar is totally different from English. It is not just about the order of the words, but also about how Japanese words are classified into its part-of-speech. Let’s see a simple example: I like banana. ’Like‘ in the sentence is a (transitive) verb. And the Japanese translation is: Banana ga suki desu. (バナナが好きです). Japanese word for ‘like’ is ‘suki’, and guess what, suki in that sentence is an adjective (precisely -な adj. or 形容動詞 keiyoudoushi). Interesting isn’t it?
Like usual, I will start my post with a disclaimer: I am not a Japanese expert. My Japanese level is still very low. I’m still struggling to master this beautiful language. However, this post is written by comparing several sources which links can be found in the end of this article (well, all of the sources are English sources. It might be better if I can have some Japanese references about Japanese part-of-speech, but unfortunately I can’t read that, sorry). If you find any mistake please let me know. And btw, this explanations are based on modern Japanese grammar (I’m not really sure but probably what considered ‘modern’ is the language after orthographic reform in post World War II, around 1946. Well, simply said, the language we use nowadays). There are some exceptions of course if we talk about poem or the like.
Okay, let’s start with the basic: noun (名詞 meishi). First type is common noun (普通名詞 futsuumeishi), general words for any people, places and things. If there is common noun, of course there is also proper noun (固有名詞 koyuumeishi), noun that refers to a specific names of an entity, person, city, planet, etc.
Nouns are nothing without their best friend: verb (動詞 doushi). Some sources say this is the most important part to understand Japanese sentences, and I think I agree with that. Japanese verbs can be divided into several types according to how they are conjugated, the object requirement, or the function. From the way they are conjugated, basically they fall into three groups. The first is group I verb (五段動詞 godandoushi). Some of you may notice the character five (五) in the name, but they are called group 1. What is happening here? The number five doesn’t come from the number of the group, but instead, comes from the variation of the forms of the word when conjugated. Here is one simple example
1) 飲まない nomanai (nai form)
2) 飲みます nomimasu (masu form)
3) 飲む nomu (dictionary form)
4) 飲めば nomeba (ba form)
5) 飲もう nomou (volitional form)
The point is that the last syllable is different for each of the five forms (ma – mi – mu – me – mo). There are several types of this type of verbs, depending on their last syllable: -u, -tsu, -ru*, -mu, -bu, -nu, -su, -ku, and -gu. (*some -ru verbs belong to group II, as will be explained below)
Next is group II (一段動詞 ichidandoushi). Similarly, the ‘ichi’ in the ‘ichidandoushi’ refers to the conjugation method. All verbs in this category have -ru ending. And there is only one way they are conjugated, which is dropping the ‘ru’ and replacing it with the proper conjugation.
Example: 食べる tabe ru (eat)
食べない tabe nai (nai form)
食べます tabe masu (masu form)
食べる tabe ru (dictionary form)
食べれば tabe reba (ba form)
食べよう tabe you (volitional form)
As we can see, in all the conjugations, the basic form of the verb is the same
The last is group III , or the irregular group. This group consists of only two verbs, i.e. する suru (to do) and くる kuru (to come). The conjugations of these verbs are irregular. Well, even though there are ‘only two’ verbs in this group, but because kuru can act as auxiliary verb and suru is also used to accommodate new and borrowed verbs, actually we find these two verbs in so many situations.
Verbs can also be categorized based on the possibility of conjugation (which of course is related to their function), like stative, continual, punctual, non-volitional, movement verbs and several other types. (Unlike the previous 3-group categorization, they can overlap to each other). But this seems to be too detailed so I will not discuss it further.
One tricky thing about Japanese verbs is the transitive and intransitive verbs. In many cases, in English we can make intransitive forms by putting the verb into passive form. For example, ‘someone start something’ & ‘something is started’. However, in Japanese there is no exact rule of how intransitive verbs are made from the transitive version. We have to memorize each of them. For example, ‘to start’ is ‘hajimeru’ (ichidandoushi group), and ‘be started’ is ‘hajimaru’ (godandoushi group).
Next, let’s take a look into adjective (形容詞 keiyoushi). Basically there are two types of adjective according to how they are conjugated with other part of speech. The first is -i adjective (形容詞 keiyoushi) and -na adjective (形容動詞 keiyoudoushi). There is a long complex story of why there are two types of adjectives like this, for example, the literal meaning of keiyoudoushi is actually adjectival-verb, so literally it is a verb. However it is not really important to understand that anyway, but the important thing is that they are different in how they are conjugated. One other important thing to note is that like verbs, Japanese adjectives have many conjugated forms, like past form or conditional form. English doesn’t have that of course.
Adverb (福祉 fukushi) is just as simply as in English I think. One important thing to pay attention is how other part of speech is conjugated to make an adjective. The most discussed topic is of course conjugation from adverb to adjective.
Well, I think those are the basics. We can already make a simple sentence using these parts. Of course there are still some other part-of-speech, and actually we will find various types of it and different categorization if we dig into the literature. For beginners like me, to master this five is already a great progress, I think.
Good luck in learning Japanese! 頑張って下さい！
*p.s.: I will write another article about simple-yet-important parts which are particles and auxiliary verbs. (Btw wikipedia calls these two parts “ancillary words” or “words of secondary importance”). See you!