Grammar
N5 verb-form

Nai-form (casual negative) 〜ない

Meaning

The plain negative of verbs. Group 1: drop final う-sound, add あnai (書く→書かない). Group 2: drop る → ない. Group 3: する→しない, 来る→来ない.

Formation

Notes

Conjugates like an i-adjective: 〜なかった (past), 〜なくて (te), 〜なければ (conditional). Base for 〜なければならない (must), 〜なくてもいい (don't have to).

Examples

I don't eat meat. (casual, Group 2)

Breakdown
meat (object) do not eat

I'm not going to school today. (casual, Group 1)

Breakdown
today (topic) school to do not go

I'm not busy tomorrow. (i-adj 〜くない, related)

Breakdown
tomorrow (topic) am not busy

I did nothing. (past negative, casual)

Breakdown
anything did not do

I don't think he'll come. (Group 3 来る→来ない)

Breakdown
he (topic) does not come I think

I don't really understand.

Breakdown
well do not understand