There are some constructions that use Nai-form of verbs. But some of them use Nai-form with a little bit of changes. In today’s construction, “Nai” of Nai-form changes to be “Nakereba”. This “nai” is an auxiliary-adjective which ends with letter “i”. Therefore, “nai” conjugates in the same way as I-adjectives. But the conjugation from “i” to “kereba” will be taught in last half in beginners’ level. At this time, simply remember that “V-nakereba naranai” desecribes obligation and/or necessity.
Learn the following sentences and try to remember them;
1. Ashita, Sensei ni Awanakereba Narimasen. (I have to meet my teacher tomorrow.)
2. Kuukou de Pasupo’oto o Misenakereba Narimasen. (I have to show my passport in the airport.)
3. Shiken Benkyou o Shinakereba Narimasen. (I need to study for examination. )
This post was written with reference to the exercise A3 on Section 17 of “Minna no Nihongo (2nd Edition)” published by “3A Corporation”