Conjugating verbs to the negative present tense in the plain form varies depending on the verb's ending. There are three types of endings we need to pay attention to:
- Group 2, or 一段 verbs, which all end in -る
- Group 1, or 五段 verbs that end in -う
- Group 1, or 五段 verbs that do not end in -う
- The irregular verbs です、ある、する、来る
For 一段 verbs, replace the -る with -ない. For example, 食べる becomes 食べない.
| I do not eat cheese because I have an allergy. | アレルギー が ある から、 チーズ を 食べない。arerugii ga aru kara, chiizu o tabenai. |
For 五段 verbs that end in -う, change the -う into -わない. For example, 買う becomes 買わない.
| Though her voice is beautiful, she doesn't sing. | 彼女 の 声 は 美しい けど、 歌わない。kanojo no koe wa utsukushii kedo, utawanai. |
For 五段 verbs not ending in -う, change the う-sound into an -あ-sound, and add ない. For example, 行く becomes 行かない.
| I won't go again. | もう 行かない。mou ikanai. |
| Although (I) don't understand it, (I) like it! | 分からない けど、 好き だ よ！wakaranai kedo, suki da yo! |
And finally, the negative plain form for the irregular verbs is as follows:
| Plain Form Positive | Plain Form Negative |
|---|---|
| だ | じゃない |
| ある | ない |
| する | しない |
| 来る | 来ない |
And here are example sentences for each of them:
| It is not the real thing. | 本物 じゃ ない。honmono ja nai. |
| Don't you have a good idea? | いい アイディア が ない か？ii aidia ga nai ka? |
| (I) won't do it. | しない。shinai. |
| I won't come today. | 今日 は 来ない。kyou wa konai. |
