A1
ません — the negative
How to form the negative of Japanese verbs and adjectives, and why the negative of です looks nothing like です.
There is no Japanese word for not. The verb’s own ending changes: ます becomes ません.
食べません。
Tabemasen.
I don’t eat it.
お酒を飲みません。
Osake o nomimasen.
I don’t drink.
Because the ending is the last thing in the sentence, you often do not know a Japanese sentence is negative until it finishes. That is worth getting used to early — it is a real difference in how you have to listen.
The plain form is ない
Below the polite ます layer, the plain negative ends in ない.
食べない。
Tabenai.
I don’t eat it.
ない is what you will meet inside longer sentences, since only the final verb takes the polite ending.
い-adjectives
They negate on the adjective, with くない.
寒くないです。
Samuku nai desu.
It isn’t cold.
です
Its negative is じゃないです — a form that shares nothing visible with です. ではありません is the formal equivalent.
学生じゃないです。
Gakusei ja nai desu.
I’m not a student.
学生ですない。
学生じゃないです。
です does not take ない on the end. It is replaced by じゃない, and です returns after it to carry the politeness.
Two irregular ones
ある — exist, for things — has ありません, which is regular. But its plain negative is ない, not あらない.
時間がありません。
Jikan ga arimasen.
There’s no time.
And いい (good) negates as よくない, from an older form よい.
いくないです。
よくないです。
いい changes to よ- before every ending: よくない, よかった. The plain form is the only place it stays いい.