Page 182 - Basic Japanese

4.9. The plain negative

The plain form of the verb arimasu ‘exists’ is aru. The

negative form of this is not a verb at all, but the adjective

nai, ‘is non-existent (= does not exist).’ The adjective nai,
then, is the plain adjective form corresponding to the polite

verb form arimasen. The plain negative of other verbs are
also adjectives derived from the verb stems by the addition

of the suffix -(a)nai—this is discussed in 5.11. Here are some
examples of the adjective nai:

Kuruma ga nai kara densha ni notte ikimasu.

I don’t have a car, so I go by train.

Kasa ga nakatta kara nurete shimaimashita.

As I did not have an umbrella, I got wet.

Koko ni oite oita no ni saifu ga nakunarimashita.
I placed it here, but my wallet disappeared
(became nonexistent).

Ukkari shite ite saifu o nakushimashita.

I was absent-minded and lost my wallet (made
it nonexistent).

Note that nakusuru is also treated as nakus-u, a consonant

verb.