昨日 Sakubi: Yesterday's Grammar Guide

Lesson 7: Negated verbs and using い-adjectives

When you turn a one-form verb into a negative verb, it cuts off the る at the end of the simple tense and adds ない.

For five-form verbs, you turn the ending "u" into an "a", with one exception.

These examples are for illustration. You should not memorize them, just understand them for now and move on.

1-form: Drop る, add ない

5-form: Replace "u" with "a", then add ない

食べない not eating / to not eat

For five-form verbs ending in う, the negative uses わない, not あない. This is that one exception.

Japanese has two types of adjectives. Don't worry, it's not the same deal as the two categories of verbs. い-adjectives act like verbs. な-adjectives act like nouns. We'll cover な-adjectives later.

Here's an example of an い-adjective in practice.

赤い火 Red fire

The reason い-adjectives "act like verbs" is because you don't use だ with them.

火が赤いThe fire is red.

"is" is only present in the translation. In fact, attaching だ here would be ungrammatical. Do not attach だ to い-adjectives.

火が赤いだ> (ungrammatical gargling)

Attaching です is okay, but です doesn't indicate state of being here, it just adds politeness. This is the first major way that だ and です are different. When it's not attached to a noun, です is just a politeness marker.

火が赤いです The fire is red.

There are more constructions that end up putting a だ or です right at the end of い-adjectives, but they don't indicate state of being like attaching だ or です to a noun does.

Like verbs, you can conjugate い-adjectives. Replace い with かった or くない.

火が赤かった The fire was red.

火が赤くない The fire is not red.

ない is an い-adjective and you can conjugate it like one.

見なかった Did not see.

Adjectives are turned into abstract nouns with さ. There are more ways to do this, but さ is by far the most common.

大きさ Size (largeness) (from 大きい)