Japanese i-adjectives also allow to express a negative meaning. It is close to adding un- to an English adjective (easy = un-easy, not easy). In order to build this form you first remove the い – I at the end of the plain form and add くない – KUNAI to the stem of the i-adjective as described in the following examples:
- 高い => 高- => 高 + くない => 高くない
- takai => taka- => taka + kunai => takakunai
| Plain Form | Romaji | Meaning | Negation | Romaji | Meaning |
| 高い | takai | high | 高くない | takakunai | not high |
| 安い | yasui | cheap | 安くない | yasukunai | not cheap |
| 美味しい | oishii | tasty | 美味しくない | oishikunai | not tasty |
| 広い | hiroi | spacious | 広くない | hirokunai | not spacious |
| 寂しい | sabishii | lonely | 寂しくない | sabishikunai | not lonely |
Example
| Kanji | 隣りのスーパーはあまり高くないです。 |
| Furigana | となりのスーパーはあまりたかくないです。 |
| Romaji | tonari no suupaa wa amari takakunai desu. |
| English | The supermarket in the neighborhood is not very expensive. |
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NIHONGO ICHIBAN 
Thank you, this chart is clear and helpful.