Lesson 23: Verbs review
We've finally run into all of the basic stems of the five-form verbs, so this is a good time to review what we've learned. Please don't try to memorize this. Knowing that these ideas exist is enough. If your eyes gloss over, relax. If you can't do it, move on.
The names given on the left are plain english representations of the japanese names. Where needed, the japanese names have alternative translations. If a form/base/stem is referred to in the rest of the guide, I'll use the plain english name, not the japanese name.
死な "none such" form ("as if it has not yet happened" 未然形)
死の tentative form
死に verb-sticky form (連用形)
死ん verb-sticky form (連用形) (reduced)
死ぬ terminal form (終止形)
死ね "some such" form ("as if it were so" 已然形 / "hypothetical" 仮定形)
死ね imperative form (命令形)
If you count, you'll identify that the base stem "shi-n" (which ends on a consonant) inflects to each of the five japanese vowels. This is what "five-form" means.
Four-form, or 四段 "yodan", shows up regularly in english writing on japanese grammar, but japanese natives literally aren't even taught the word anymore.
One-form verbs look like so:
食べ "none such" form ("as if it has not yet happened" 未然形)
食べ tentative form *
食べ verb-sticky form (連用形)
食べる terminal form (終止形)
食べれ "some such" form ("as if it were so" 已然形 / "hypothetical" 仮定形)
食べろ imperative form (命令形)
As you can see, there's a lot more irregularity here, but the verb's base kana stem never changes, hence the name one-form. The one and only base.
This is the set of classical bases, aside from modernization: including the reduced verb-sticky form and the tentative, and excluding the attributive.
The "none such" form is used for negatives, passives, and some condition expressions. It's also the etymology of the tentative form.
The tentative form is the base of the volitional/hortative ～おう/よう forms.
The terminal form is, for normal dictionary verbs, the plain "non-past" tense.
The verb-sticky form is used for most of the complex verb conjugations in japanese, including the ます form, past, て form, たい form, etc.
The "some such" form is used in some conditions and is sometimes considered the base of the short potentials.
The imperative form is an imperative form. It forms rough commands.
Traditional japanese grammar analyzes the long potential form of one-form verbs as られる itself attached to the base stem, not れる attached to a ら. There's no difference between the two interpretations.
The only reason for the one-form verbs to have a 未然形 form, in addition to the identical verb-sticky form, is so that grammarians don't need to give one-form verbs their own rule for the negative. Yes, it's silly.