Negative Perfective Form
This form expresses an event that did not take place.
How to derive the Negative Perfective form:
If you are familiar with the formation of the negative imperfective form, then you need to know only one rule, which is to change the final い of the negative imperfective form to なかった.
If you need to review the negative imperfective form before adding the perfective aspect, then the following are the rules for deriving the negative perfective form:
- Group 1: Change the final る to なかった
- Group 2: Change the final vowel u to a and add なかった
- Group 3: くる→こなかった、する→しなかった
Exception: the negative perfective form of ある is なかった.
Consider the single vowel u （う） at the end of certain verbs such as kau （かう） as having the hidden consonant w before the vowel u. In other words, the original form of kau （かう） is ka(w)u. This information is important when the last vowel u changes to a in the negative perfective form before adding nakatta （なかった）. The negative perfective of kau （かう） therefore is kawanakatta （かわなかった） rather than kaanakatta （かあなかった）.
How to use the form:
When this verb form is used in speech at the end of a sentence, it indicates casual speech. When used in writing, this form indicates that the writing is impersonal (such as newspaper articles, essays, journals, etc.).
'I did not study yesterday.'