Nevertheless, at least one conjugation is always common to Japanese learners and native speakers. A plain form is it. In Japanese it’s called shūshikei. So their names are different, but their concept is the same. In this blog post, I will explain a plain form of verbs, i-adjectives and na-adjectives. And also, I will explain how to make plain formed words as well.
- Definition of plain form
- Verb in plain form
- I-adjective in plain form
- Na-adjective in plain form
Definition of plain formAs the name suggests, words in plain form are plain, in other words, unprocessed. So usually flash cards and dictionaries show words in plain form. This form is really important as the first step of Japanese vocabulary and also the base of Japanese conjugations.
As I already mentioned, its Japanese name is shūshikei. In order to have a better understanding, let me explain components of its name.
- shushi – 終止 (しゅうし) : a noun to mean ‘end’ or ‘termination’.
- kei – 形 (けい) : a noun to mean ‘form’, ‘type’, ‘shape’ and so forth.
By the way, I strongly recommend that Japanese learners should break down words into their components in a similar way that I did here. This method would be helpful to assume meaning of words which are completely new to them. Actually, even native speakers often do the same thing.
In the following paragraphs, I will explain a plain formed verb, i-adjective and na-adjective one by one.
Verb in plain formLet’s start with a verb.
Before explanations, let me check new words here.
- watashi – 私 (わたし) : a pronoun which corresponds well to “I”.
- wa – は : a binding particle working as a case maker or topic maker. Here, it works as a case maker and helps the pronoun, “watashi”, to become the subject.
- kyoto – 京都 (きょうと) : a noun which is a name of one of the most famous Japanese cities.
- ni – に : a case particle to express a place where something or someone is. It often corresponds to “at” or “in”.
- iru – いる : a plain formed verb which corresponds well to English be verbs. Depending on context, it means ‘to stay’. Learn more about iru.
I know there are several Japanese verbs classified into ru verbs. “Iru” is one of them. However, even ru verbs end with “u” in plain form. As long as verbs are in plain form, they end with “u”. Certainly, there are several exceptions, but we don’t have to worry about them that much. They appear only in Japanese old literature. Today Japanese people don’t use them at all.
Again, a plain form is the base of Japanese conjugations. So conjugations of Japanese verbs are based on their plain form. When we need to consider their conjugations, we replace the last vowel in plain form, so “u”, with something else. It totally depends on a conjugation which we need to consider. Sometimes it would be another vowel. Sometimes it would be a combination of a consonant and vowel.
How to change iru to its imperative formI will show you how to change “iru” to its imperative form. Usually Japanese verbs end with a vowel, “o”, in their imperative form. So here only we need to do is replacing the last vowel, “u”, with “o”.
Very easy. This is one example showing how to make another form based on a plain form. The next point would be how to make a plain form.
How to make plain formed verbsThis is a bit more difficult than making other conjugations based on a plain form. In order to understand a way to make it, first we need to know a stem part and conjugative suffix of word.
Japanese verbs, i-adjectives and na-adjectives consist of a stem part and conjugative suffix. A stem part plays a main role of word. It works to express meaning. If it changes, meaning could also change. So normally it will never change and is common to all conjugations. On the other hand, a conjugative suffix usually changes as a word is conjugated. Usually the last hiragana character is it.
For example, “iro” is an imperative form of the verb “iru”. As shown above, their hiragana expressions are いろ and いる respectively. So here we can see い is its stem part and never changes and both ろ and る are conjugative suffixes.
This is the relation between the stem part and conjugative suffix. Then, in order to make “iru いる” from “iro いろ”, we need to replace the conjugative suffix “ro ろ” with “ru る”. In alphabets, we need to replace the last vowel “o” in its imperative form with “u”. These two conjugative suffixes share the same consonant, “r”, so a method using alphabets leads to the same result as a hiragana method does. However, sometimes, conjugative suffixes don’t share the same consonant. Therefore, we need to understand the alphabet method does not always work well. In principle, Japanese conjugations are based on Japanese writing system.
I-adjective in plain formThen let’s take a look at an example with a plain formed i-adjective.
Let me check a new word here.
- utsukushii – 美しい (うつくしい) : an i-adjective to mean ‘beautiful’. Learn more about utsukushii.
As I mentioned above, i-adjectives also consist of a stem part and conjugative suffix. In plain form, the vowel, “I い”, is a conjugative suffix. And the rest is a stem part. When we need to conjugate i-adjectives, we have to replace the last vowel, “I い”, with another conjugative suffix. Sometimes it would be another vowel. Sometimes it would be a combination of a consonant and vowel.
How to change utsukushii to its nai formBelow is how to change utsukushii to its nai form.
From the grammatical point of view, a word, “nai”, itself is not a part of the conjugation. So now I compare “utsukushii うつくしい” with “utsukushiku うつくしく” only. As we can see here, “utsukushi” is common to both forms, so it would be the stem part. Other parts, “ku く” and “I い” are conjugative suffixes. By replacing “I い” with “ku く”, I changed “utsukushii うつくしい” to another conjugation which fits with “nai”. Usually, conjugative suffixes are the last hiragana character of i-adjectives. Sometimes, however, two characters form a suffix. We need to be careful with exceptions. In a way, making conjugations based on a plain form always presupposes knowledge of vocabulary.
By the way, I choose a nai form for the example here while I used an imperative form as an example for verbs above. This is because there is not imperative form for i-adjectives.
How to make plain formed i-adjectiveThen I will explain how to make plain formed i-adjectives. By replacing a conjugative suffix with the vowel, “i い”, we can make plain formed I-adjectives easily. For instance, in the case of “utsukushiku うつくしく”, we only need to replace “ku く” with “i い”. Very easy as long as we can distinguish a conjugative suffix from a stem part.
Na-adjective in plain formThen check an example with a na-adjective.
Here is one new word.
- kireida – 綺麗だ (きれいだ) : a na-adjective to mean ‘beautiful’. Learn more about Kireida.
To tell the truth, from the Japanese grammatical point of view, na-adjectives need to end with “da” in their plain form. A form ending with “na” is not a plain form really. This fact would be confusing, but don’t worry that much. Now I’m talking about conjugative suffixes of na-adjectives, but they are not so important. Basically, a stem part of na-adjective is a noun. And its conjugations are more or less the same as those of the stem part itself. Plus, Japanese native speakers often omit conjugative suffixes of na-adjectives. Furthermore they use the stem part itself like an adjective in conversation, it is a noun though.
For these reasons, conjugative suffixes of na-adjective are not that important. Therefore the difference in their names is not important as well. Nevertheless, I will focus on them. In the following paragraphs, I will explain how to make another conjugation from a plain form.
How to change kireida to its nai formBelow is how to change kireida to its nai form.
In a similar way that I did for “utsukushii”, I focus on conjugative suffixes, “da だ” and “de で”, only. By replacing “da だ” with “de で”, we can change “kireida きれいだ” to another conjugation, “kireide きれいで”, which fits with “nai”. Now distinguish conjugative suffixes from a stem part is very easy. Due to the trait of na-adjective explained above, we only need to find out a noun. It is a stem part. And others are conjugative suffixes. Not difficult at all. Even in two hiragana characters form a conjugative suffix, we can easily find a stem part.
Here, for the same reason as I did for an i-adjective above, I chose a nai form as an example.
How to make plain formed na-adjectiveOnly we have to do is considering the above method in the opposite direction. By replacing a conjugative suffix with “da だ”, we can make plain formed na-adjectives. In the case of “kireide きれいで”, we just replace “de で” with “da だ”.
Or perhaps, we can use the trait of na-adjectives. We can make a plain formed na-adjective by just adding “da だ” at the end of noun. This method doesn’t always work well, but would be useful especially to make a new adjective-like noun.
SummaryLet me summarize what I’ve explained in this blog post as follows.
- In Japanese, verbs, i-adjectvies and na-adjectives consist of a stem part and conjugative suffix.
- Verbs end with a vowel, u, in plain form. We can make plain formed verbs by replacing a conjugative suffix with u or a combination of a consonant and u.
- I-adjectives end with a vowel, I, in plain form. We can make plain formed i-adjectives by replacing a conjugative suffix with i.
- Na-adjectives end with da in plain form. We can make plain formed na-adjectives by replacing a conjugative suffix with da. Adding da at the end of noun would be another way to make them.
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I am trying to spread the Japanese culture through teaching the Japanese language. One of my goals is to make Japanese learners feel the culture through the language.