はじめに - Hajime ni

Today's lesson focuses on い(i)-adjectives and な(na)-adjectives. Understanding these two types of adjectives is crucial for building descriptive sentences in Japanese, which is very common in JLPT N5 questions and daily conversations. You'll learn how to modify nouns with them and how to use them to describe things and people directly.

文(ぶん)の作(つく)り方(かた) - Bun no Tsukurikata

In Japanese, adjectives describe qualities, characteristics, or states of nouns. There are two main categories: い(i)-adjectives and な(na)-adjectives. The key difference lies in their endings and how they connect to nouns or predicate sentences.

1. い(i)-Adjectives:

• These adjectives always end in い(i) when they directly precede a noun or end a sentence in their dictionary form.

• The い(i) is part of the adjective stem itself.

  Structure 1: Modifying a Noun い(i)-Adjective + Noun 例(れい): 高(たか)い (takai) (expensive) + 本(ほん) (hon) (book) = 高(たか)い本(ほん) (takai hon) (an expensive book)

  Structure 2: Predicating a Sentence (ending a sentence) Noun は (wa) い(i)-Adjective です (desu). 例(れい): この本(ほん)は高(たか)いです。(Kono hon wa takai desu.) (This book is expensive.)

2. な(na)-Adjectives:

• These adjectives often describe states or qualities, but they do not end in い(i) in their dictionary form (though some might end in -な).

• When they directly precede a noun, you must add な(na) between the adjective and the noun.

• When they end a sentence, な(na) is not used, and they are typically followed by です (desu).

  Structure 1: Modifying a Noun な(na)-Adjective + な(na) + Noun 例(れい): きれい (kirei) (beautiful/clean) + な(na) + 花(はな) (hana) (flower) = きれいな花(はな) (kirei na hana) (a beautiful flower)

  Structure 2: Predicating a Sentence (ending a sentence) Noun は (wa) な(na)-Adjective です (desu). 例(れい): あの花(はな)はきれい(kirei)です。(Ano hana wa kirei desu.) (That flower is beautiful.)

Key Differences Summarized:

文(ぶん)化(か)的(てき)な背(はい)景(けい) - Bunkateki na Haikei

In Japanese culture, describing things politely is important. The use of です (desu) at the end of adjective sentences makes them polite and suitable for most social situations. While informal forms exist (dropping です for い(i)-adjectives or changing です to だ for な(na)-adjectives), it's best to stick with the polite forms when speaking to people you don't know well, elders, or those in a higher social position.

Adjectives like きれい (kirei) can mean both "beautiful" and "clean." The context often clarifies the meaning. For example, きれいな部屋(へや) (kirei na heya) typically means "a clean room," while きれいな景色(けしき) (kirei na keshiki) means "a beautiful scenery." This nuance reflects an appreciation for cleanliness as a form of beauty in Japan.

例文(れいぶん) - Reibun

Here are 10 distinct example sentences using い(i)-adjectives and な(na)-adjectives:

1. これは高(たか)い時計(とけい)です。 (Kore wa takai tokee desu.) This is an expensive watch.
2. この本(ほん)はとても古(ふる)いです。 (Kono hon wa totemo furui desu.) This book is very old.
3. あのかばんは大(おお)きいです。 (Ano kaban wa ookii desu.) That bag is big.
4. それは小(ちい)さい猫(ねこ)ですね。 (Sore wa chiisai neko desu ne.) That is a small cat, isn't it?
5. 日本語(にほんご)の勉強(べんきょう)は難(むずか)しいです。 (Nihongo no benkyoo wa muzukashii desu.) Japanese study is difficult.
6. あの店(みせ)は有名(ゆうめい)なレストランです。 (Ano mise wa yuumei na resutoran desu.) That store is a famous restaurant.
7. この部屋(へや)はとても静(しず)かです。 (Kono heya wa totemo shizuka desu.) This room is very quiet.
8. 私(わたし)の町(まち)はにぎやかです。 (Watashi no machi wa nigiyaka desu.) My town is lively.
9. 彼(かれ)は親切(しんせつ)な人(ひと)です。 (Kare wa shinsetsu na hito desu.) He is a kind person.
10. この公園(こうえん)はきれいな公園(こうえん)です。 (Kono koen wa kirei na koen desu.) This is a beautiful/clean park.

練習(れんしゅう)問題(もんだい) - Renshū Mondai

A. Choose the correct form of the adjective (い(i) or な(na)) to complete the sentences. (Select either い(i) or な(na), then add the appropriate adjective form.)

1. これは新(あたら)し＿＿(い/な)辞書(じしょ)です。 (This is a new dictionary.)
2. 日本(にほん)の町(まち)はきれ＿＿(い/な)です。 (Japanese towns are beautiful/clean.)
3. 彼(かれ)は元気(げんき)＿＿(い/な)です。 (He is fine/healthy.)
4. あの映画(えいが)は面白(おもしろ)＿＿(い/な)です。 (That movie is interesting.)
5. 私(わたし)の家(いえ)は小(ちい)さ＿＿(い/な)です。 (My house is small.)

B. Translate the following sentences into Japanese, paying attention to adjective usage.

1. This bag is new.
2. That is a quiet classroom.
3. Japanese cars are expensive.
4. My younger brother is very kind.
5. Is your room clean?

練習(れんしゅう)問題(もんだい)の答(こた)え - Renshū Mondai no Kotae

A. Choose the correct form of the adjective (い(i) or な(na)) to complete the sentences.

1. これは新(あたら)しい辞書(じしょ)です。
2. 日本(にほん)の町(まち)はきれいです。
3. 彼(かれ)は元気(げんき)なです。
4. あの映画(えいが)は面白(おもしろ)いです。
5. 私(わたし)の家(いえ)は小(ちい)さいです。

B. Translate the following sentences into Japanese.

1. このかばんは新(あたら)しいです。 (Kono kaban wa atarashii desu.)
2. それは静(しず)かな教室(きょうしつ)です。 (Sore wa shizuka na kyooshitsu desu.)
3. 日本(にほん)の車(くるま)は高(たか)いです。 (Nihon no kuruma wa takai desu.)
4. 私(わたし)の弟(おとうと)はとても親切(しんせつ)です。 (Watashi no otooto wa totemo shinsetsu desu.)
5. あなた(or あなたの部屋(へや))はきれいですか。 (Anata (no heya) wa kirei desu ka?)