68490
I've heard that the non-past negative form ends in nai. However, other forms
will aswell have na alone (na katta). Is there some meaning behind this い or
is that how the form is?
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2019-05-26T01:22:55.267
68486
2019-05-26T08:36:01.863
34145
question
grammar conjugations negation
What's the い in ない?
That's how the form is. い-Adjectives in Japanese are a bit like verbs - they
have many (but not all) of the same inflections that verbs do, and often those
inflections mean the い gets replaced with something else. This is just like
the final -う or -る of verbs getting replaced when they get inflected.

Here are some examples with 食{た}べ (eat) and 美味{おい}しい (tasty):

  * simple past: 食べた, 美味しかった
  * conditional (tara) form: 食べたら, 美味しかったら
  * "hypothetical" (ba) form: 食べれば, 美味しければ
  * te-form: 食べて, 美味しくて (note: 美味しくて does not mean "be delicious!")
  * negative: 食べない, 美味しくない

And relevant to your example:

  * past negative: 食べなかった, 美味しくなかった

So ～なかった is just the past version of ～ない.
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2019-05-26T02:42:30.170
68488
2019-05-26T02:42:30.170
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answer
In Standard Japanese, the negative particle (auxiliary) has been totally
conflated with the adjective ない "not exist" in form. And in older language,
the form corresponds to ない was なき (naki), so it was sharing the last _-k_ with
other forms. It seems somewhat irregular only after the _k_ -sound dropped
before _i_. Some dialects drop _k_ before other vowels, which makes
conjugation more complex (See
[1](https://japanese.stackexchange.com/q/24217/7810),
[2](https://japanese.stackexchange.com/q/42890/7810)). It is not uncommon that
velar consonants disappear in the middle of word.

> English _sail_ < Old English _segel, segl_ (cf. German _Segel_ )  
>  English _royal_ < French _royal_ < Latin _regalis_

By the way, the perfect (past) form なかった (nakatta) is originally a contraction
of なく (naku) + あった (atta "was").
CC BY-SA 4.0
2019-05-26T05:58:33.787
68490
2019-05-26T08:36:01.863
2019-05-26T08:36:01.863
7810
7810
68486
answer