Mastering Japanese Adjectives: A Comprehensive Tutorial

If you want a thorough and easily digestible resource on Japanese adjectives, you’ve landed in the right place.

Adjectives are a vital element of the Japanese language, serving to describe, identify, and differentiate nouns. It’s hard to picture a world devoid of adjectives – as poetry, romance, and emotions would vanish.

If you’re grappling with い-adjectives and な-adjectives and haven’t yet mastered their conjugations, we can help! I’m excited to present a comprehensive overview of Japanese adjectives to help broaden your vocabulary.

Please note that romanization will not be included in this article, as it’s assumed you’re already familiar with the Japanese writing system. If not, consider using the Bunpo app for free to get caught up, or refer to the hiragana charts.

So, grab your notebooks, and let’s dive into learning Japanese adjectives!

Japanese Adjectives

Japanese adjectives are primarily divided into two categories: い-adjectives and な-adjectives. Let’s go over both to ensure we know each kind’s uses. 

い-adjectives

We’ll begin with い-adjectives. The most noticeable feature of い-adjectives is their “い” ending. Like English adjectives, い-adjectives mainly modify nouns or function as predicates in a sentence. Now, let’s explore how to conjugate い-adjectives.

Basic Conjugation

Like English, Japanese is a language with tenses. Japanese has only two tenses—present/future tense and past tense—while English has 16. Another distinction is that only verbs are conjugated in English, but both verbs and adjectives are conjugated in Japanese.

In English, adjectives are negated by adding “no” or “not” before them, e.g., “The man is not tall.” In Japanese, however, negative statements are formed by conjugating adjectives.

For example, consider the い-adjective “たかい” meaning “expensive.” The table below shows its four basic conjugations. If you’re not familiar with them, it’s essential to learn them quickly as a beginner.

Present / Future VS Past

Positive たかい (it is expensive) /  たかかった (it was expensive)

Negative たかくない (it is not expensive) / たかくなかった (it was not expensive)

As you can see in the above examples, if we want to make an adjective in the past tense, we replace the い with かった. For example, the adjective さむい meaning “cold” would be さむかった in the past tense, meaning “it was cold.”

To negate an い adjective, we simply remove the い ending and add くない. So our previous example of さむい becomes さむくない, meaning “it is not cold.” 

And to add them both together in the negative past tense, we take the last い in さむくない and replace it with かった again to make さむくなかった which means “it was not cold.”

Now, let’s take a look at a few more sentences to understand the basic conjugation of い-adjectives.

車はたかい – The car is expensive

このレストランはたかくない – This restaurant is not expensive

 その本はたかかった– The book was expensive

去年、そのチケットはたかくなかった – Last year, the tickets were not expensive

Positioning い-adjectives in Japanese

Once you’re comfortable with the four basic conjugations of い-adjectives mentioned earlier, let’s examine how い-adjectives are utilized in sentences. 

At the end of a sentence

When an い-adjective appears at the end of a sentence, it’s referred to as a PREDICATIVE adjective. Keep in mind that this case is also common in English. The example sentences in the Basic Conjugation section are instances of い-adjectives occurring at the end of a sentence.

車はたかい – The car is expensive

このレストランはたかくない – This restaurant is not expensive

As a beginner, you should be aware that Japanese is a language with an honorific system, which distinguishes between polite and casual speech.

The example sentences above are all in casual speech. To convert them into polite speech, simply add “です(desu)” at the end of the sentences.

車はたかいです – The car is expensive

このレストランはたかくないです – This restaurant is not expensive

Before a noun

Similar to many English adjectives, い-adjectives can be placed before a noun as ATTRIBUTIVE adjectives, this is how we describe nouns in Japanese.  Let’s look through some examples:

たかい車 – expensive car

昨日、おもしろくない本を読みました – I read an uninteresting book yesterday

In the examples above, the い-adjectives, たかい and おもしろくない, are both in the present/future tense, regardless of the positive or negative statement. 

So, can past tense い-adjectives appear before a noun? The answer is that it depends. Generally, when past tense い-adjectives precede a noun, they convey a sense of change. As a result, they can’t be used for something constant.

たかかった車 ×

おもしろくなかった本 〇

せまかった庭 〇

The first sentence has no grammatical errors, but it doesn’t sound natural to Japanese speakers.

The second sentence is correct. A book that was once boring has become interesting (to me) for some reason. Similarly, in the third sentence, the garden was narrow, but maybe it was widened and is not longer narrow.

In the middle of a sentence

い-adjectives can also appear in the middle of sentences. In this case, they connect two simple sentences to form a compound sentence. If you’re not sure what a compound sentence is, the following example might help.

That place was bad and the people were not nice.

In the sentence above, “and” connects two simple sentences, creating a compound sentence. Got it? So, how do we combine two simple sentences with い-adjectives in Japanese?

That place was bad – あの場所はわるかった

The people were not nice – 人々がやさしくなかった

To answer this, let’s introduce another conjugation of い-adjectives – the te-form (て形). By changing the い ending of an い-adjective to くて (わるい → わるくて), we can create its te-form. The te-form is used to connect two simple sentences.

あの場所はわるくて、人々がやさしくなかった。

That place was bad, and the people were not nice. 

You might be wondering about the tense of a te-form い-adjective. Well, it doesn’t have a tense. We can only determine a sentence’s tense by its ending. In the example above, “わるかった” indicates that it’s a past tense sentence.

In this example, the place was bad (わるい), but what if it wasn’t so bad (わるくない)? Simply change the ending い to くて: わるくない→わるくなくて.

あの場所はわるくなくて、人々もやさしかった。

That place was not bad, and the people were nice.

な Adjectives

Unlike い-adjectives, which have conjugations to indicate tense, な-adjectives cannot be conjugated in this way. Instead, they are often referred to as “nominal adjectives” or “adjectival nouns” because they function more like nouns than traditional adjectives. While な-adjectives do not have specific tenses, they can be modified with other words like adverbs to indicate time or degree.

Although な adjectives end in な, this is sometimes omitted completely, so they can easily be confused with nouns. 

Some common な type adjectives are べんりな and ゆうめいな. Let’s take a look at how to use these in a few sentences to understand how they work. 

な-adjectives in sentences

Similar to い-adjectives, な-adjectives can also be used in various sentence positions, such as at the end of the sentence, before a noun, and in the middle of a sentence. Let’s take a look at some examples.

At the end of a sentence:

彼女はゆうめいです – She is famous

このレストランはべんりです – This restaurant is convenient

As you can see from the examples above, when we use な adjectives at the end of the sentence, we don’t need to use な, it is fine to just add です to make the sentence polite, or だ if it is more casual. 

Before a noun:

ゆうめいな場所 – famous place

べんりな道 – convenient road

When we place a な adjective before a noun, we need to use the な to make sure we know that we are describing that specific word. 

In the middle of a sentence:

彼女はゆうめいで、性格もいいです – She isfamous and has a good personality.

このレストランはべんりで、食べ物はおいしいです。 – This resaurant is convenient and the food is delicious.

In the above examples you can see that if we want to use a compound sentence, we can use で, which is similar to how we used くて with い adjectives. This uses the same て form to connect two sentences together. 

As you can see, な-adjectives are quite similar to い-adjectives in terms of sentence usage. However, the main difference lies in their conjugation. While い-adjectives change their endings, な-adjectives remain the same and instead use the particle な before a noun or the particle で in the middle of a sentence to connect two simple sentences.

Conjugating な-adjectives

The conjugation of な-adjectives is relatively simple compared to い-adjectives. You don’t need to change the endings of the adjectives themselves. Instead, you will use auxiliary verbs or particles to express different tenses or negations. Here’s a quick overview:

Present / Future Past

Positive な-adjective + です な-adjective + でした

Negative な-adjective + じゃないです / ではないです な-adjective + じゃなかったです / ではなかったです

Examples:

べんりです – It is convenient.

べんりでした – It was convenient.

べんりじゃないです (or べんりではないです) – It is not convenient.

べんりじゃなかったです (or べんりではなかったです) – It was not convenient

You can notice that な-adjectives don’t change their endings at all. The main change occurs in the auxiliary verb です and its negative counterparts じゃないです/ではないです, as well as their past tense forms でした and じゃなかったです/ではなかったです.

While both い and な adjectives share similarities in their functions and sentence positions, their conjugation patterns differ. い-adjectives change their endings, while な-adjectives use auxiliary verbs and particles to convey different meanings. By mastering these two types of adjectives and their conjugation rules, you’ll be well on your way to becoming more proficient in Japanese.