Grammar Info

N5 Lesson 6: 7/13


Was not, Wasn't (Adjective)


[い]Adjective[く]+ なかった

おもしろ + なかった
(あたら) + なかった


  • Part of Speech


  • Part of Speech

    Auxiliary Verb

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  • 品詞


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About い-Adjective くなかった

In order to create the negative past form of い-Adjectives, we will need to use the conjugation form. The conjugation form of an い-Adjective is simply created by removing the い, and replacing it with く. く is then followed by ない (conjugated into its past form なかった), or あります (conjugated into its past negative form ありませんでした).

The polite negative (past) form requires use of the う - Verb, ある. This is not a unique rule for the negative past, but actually the correct way that all く-form conjugations of い-Adjectives should be constructed. However, in modern Japanese, it is not considered necessary. Instead, the semi-polite form is often used.

The semi-polite form is constructed by using なかった, and then simply adding です.




    The coffee was not hot.


    That was not cheap.


    My dog was not strong.


    My (older) sister's house was not expensive.


    Reading manga was not difficult.

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い-Adjective くなかった – Grammar Discussion

Most Recent Replies (4 in total)

  • nekoyama


    I don’t know the reason, it’s just how the language evolved.

    When you say that in order to make a verb polite, one conjugates the stem, what happens is that the auxiliary ます is attached to the verb, and ます has to be attached to the 連用形 (aka masu stem). For adjectives, a way to attach ます directly to the 連用形 (the く form) just never appeared. So that’s why it’s not just 連用形 + ます.

    Now where does the あり come from? First, the reason い-adjectives can function like verbs (e.g. as a predicate) is that the い-form includes a “to be” meaning - but the く form does not. But since we can use it adverbially, we can just add a verb to add the “to be” meaning, like ある, and then we can make that verb polite because we know how to make verbs polite. It doesn’t have to be this way, but it’s something we can do.

    For example, in order to make 美味しい polite, we can use it as an adverb paired with the polite あります and get 美味しくあります. Like I wrote, it doesn’t have to be this, and there are ot...

  • mrnoone


    @nekoyama @Superpnut

    Adding to nekoyama answer, the ありません comes from the negative polite form of the ある.
    In other words, with verbs, you simply attach ない to the stem, while for いadjectives you technically attach the negative form of ある.

    It all comes way back to classical Japanese, where いAdjectives were called く adjectives. Unlike now, where い of いadjectives conjugates (which is fairly simple) the copula あり (similar to だ and です which are modern copulas, that is words linking predicate to the subject, putting it simply “to be”) had to be added to くadjective so:

    Adjective: (寒い cold (weather)
    Now: 寒い
    Classical Japanese: 寒くあり (isn’t it complicated? Japanese thought the same, so it was replaced with い eventually)

    Fun fact 1

    By the way, ある is the attributive form of the same あり (the form used to describe/modify nouns).<...

  • Superpnut


    Oh that makes a bunch of since thanks for saying it in simple terms so I can understand it

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