Explanatory の / んだ / んだけど / んですが (IMPORTANT GRAMMAR)

Today, we’re going to learn how to use の(no) to explain things. This article covers the concepts covered in this video. I recommend you watch the video first and read this whenever you want to review.

 

Using の as an Explanatory Particle

As you may already know, の is often used as a possessive particle.

noun 1 の noun 2
noun 1‘s noun 2

みさのピカチュウ
Misa no Pikachuu
Misa‘s Pikachu

本ほんの一部いちぶ
hon no ichi bu
a part of a book

エルフの耳みみの形かたち
Erufu no mimi no katachi
the shape of an elf‘s ears

However, there’s another way you can use の. You can put it at the end of a question when you are curious and want an explanation from someone.

何なにそれ？おいしいの？
Nani sore? Oishii no?
What’s that? (Tell me) Is it yummy?

This phrase is famous on the internet. It’s a sarcastic comment that is slang for, “I don’t know what that means.”

For example, suppose you say to yourself:

猫ねこ本当ほんとうにかわいいな〜
Neko hontou ni kawaii na~
Cats are really cute.

*The な at the end makes it sound like you’re talking to yourself.

Your friend overhears you and asks:

なんで猫ねこ(を)飼かわないの？
Nande neko (wo) kawanai no?
Why don’t you get a cat? (Tell me why! I’m curious.)

You answer:

犬いぬを飼かっている。
Inu wo katteiru.
I have a dog.

の is often paired with either なんで(nande) or どうして(doushite).

なんで/どうして〜の
Nande/ Doushite〜no
Why〜? (Tell me why! I’m curious.)

To make it more formal, you can change の into んですか (~ndesuka).

どうして猫ねこを飼かわないんですか。
Doushite neko wo kawanain desu ka.
Why don’t you get a cat? (Tell me why! I’m curious.)

So how is this sentence different without の?

どうして猫ねこを飼かいませんか。
Doushite neko wo kaimasen ka.
Why don’t you get a cat?

Both sentences have the same meaning, but when you add の, it feels more natural, and it gives the impression that you’re interested in knowing why they don’t have a cat. Without の, you somewhat sound like a textbook or robot. It’s the same when you’re answering:

猫ねこアレルギーです。
Neko arerugii desu.
I have a cat allergy.

Without の, it sounds like you’re just making a statement. Instead, you can add ん before です like this:

猫ねこアレルギーなんです。
Neko arerugii nandesu.
I have a cat allergy. (That’s why…)

In this sentence, we shortened の to ん and added だ.

んだ/の/んです
noun + な + explanatory particle.

猫ねこアレルギーなんだ。(casual)
Neko arerugii nanda.
猫ねこアレルギーなの。(feminine)
Neko arerugii nano.
猫ねこアレルギーなんです。(formal)
Neko arerugii nan desu.

*Here, we add な(na) since アレルギー, or allergy, is a noun.

Typically, you can just use んだ. The formal version is んです, and の sounds feminine and a little childish.

You may be wondering why we can’t just use から(kara), which means, “because”.

猫ねこアレルギーだから、飼かえない。
Neko arerugii dakara, kaenai.

The meaning is the same, but using から here feels unnatural, like there is a correct answer to the question. It feels more natural to use の. It’s similar to English, where it’s common to leave out the word “because”.

どうして遅おくれたの。
Doushite okureta no.
Why are you late?(Tell me why.)

渋滞じゅうたいに巻まき込こまれたんだ。
Juutai ni maki komaretan da.
I got caught in traffic. (That’s why…)

どうしたの？
Doushita no?
どうしたんですか？
Doushitan desu ka?
What’s wrong?/What happened?

You can also just say どうした？(doushita?), but it feels rough.

お腹なか痛いたいんだ。
O-naka itain da.
My stomach hurts. (That’s why I’m like this…)

みさ、悲かなしそう…どうしたの？
Misa, kanashisou… doushita no?
Misa, you seem sad… What’s wrong? (Tell me!)

指輪ゆびわをなくしたんだ。
Yubiwa wo naku shitan da.
指輪ゆびわをなくしたの。
Yubiwa wo naku shita no.
I lost my ring. (That’s why…)

元気げんきなさそうだね。
Genki nasasou da ne.
You don’t seem well.

風邪かぜ引ひいたんだ。
Kaze hiitan da.
I caught a cold. (That’s why…)

なんで泣ないてるの?
Nande naiteru no.
Why are you crying?

You can say the same thing without の, but then it feels cold, like you don’t really care.

なんで泣ないてる？
Nande naiteru?
どうして泣ないていますか？
Doushite naiteimasu ka?

All of the examples so far have been sad, but of course, you can use の when you’re happy, too. Suppose your friend says to you:

嬉うれしそうだね。
Ureshisou da ne.
You seem happy.

You reply to her:

もうすぐ新あたらしいポケモンのエキスパンションパスが配信はいしんされるんだ。
Mou sugu atarashii Pokemon no ekisupanshon pasu ga haishin sarerun da.
A new Pokémon expansion pass will be released soon. (That’s why!)

* 配信はいしん (haishin) is used for things that can be downloaded, but not physical games.

Or maybe you’re happy because you just passed the JLPT.

日本語能力試験にほんごのうりょくしけんに合格ごうかくしたんだ。
Nihongo nouryoku shiken ni goukaku shitan da.
日本語能力試験にほんごのうりょくしけんに受うかったんだ。
Nihongo nouryoku shiken ni ukattan da.
I passed the JLPT. (That’s why!)

 

Using の when You Want to Start a Conversation

Remember that you use explanatory particles when you’re explaining something. You don’t use them when you’re just announcing it on Facebook.

日本語能力試験にほんごのうりょくしけんに合格ごうかくした。
Nihongo nouryoku shiken ni goukaku shita.
日本語能力試験にほんごのうりょくしけんに受うかった。
Nihongo nouryoku shiken ni ukatta.
I passed the JLPT.

However, there is a situation where you can use explanatory particles other than when you explain it to someone.

You can use 〜んだ when you want to start a conversation, change the subject, or talk about something new. It’s similar to “So…” or “By the way” in English.
If you just passed the JLPT, and you want your friends to ask you about it, you might say:

そういえば、日本語能力試験にほんごのうりょくしけんに合格ごうかくしたんだ。
Sou ieba, Nihongo nouryoku shiken ni goukaku shitan da.
By the way/Speaking of which, I passed the JLPT. (Guess what! Ask me about it!)

昨日きのう新あたらしい本ほんを買かったんだ。
Kinou atarashii hon wo kattan da.
So… I bought a new book yesterday. (Ask me about it!)

昨日きのうかわいいカフェに行いったんだ。
Kinou kawaii kafe ni ittan da.
So… I went to a cute cafe yesterday.

This is conversational, so it’s not normally used for short announcements on social media. On the other hand, you will see 〜んだけど(~ndakedo) and 〜ですが(~ndesuga) on Facebook and Twitter.

昨日きのう新あたらしい本ほんを買かったんだけど、まじで面白おもしろい。
Kinou atarashii hon wo kattan dakedo, maji de omoshiroi.
I bought a new book yesterday, and it’s SO interesting.

〜んだけど/〜んですけど/〜んですが
〜n dakedo/〜n desu kedo/~n desu ga

けど and が are translated as “but” and are used to connect two clauses. Be careful no to use でも(demo), which also means “but”, but is used only at the beginning of a sentence.

買かいたいけど、高たかすぎる。
Kaitai kedo, takasugiru.
I want to buy it, but it’s too expensive.

Formal:
買かいたいですが、高たかすぎます。
Kaitai desu ga, takasugimasu.
I want to buy it, but it’s too expensive.

新あたらしいゲームをやり始はじめたんだけど、本当ほんとうに楽たのしい。
Atarashii geemu wo yari hajimetan dakedo, hontou ni tanoshii.
I started playing a new game, and it’s really fun.

A common mistake among beginners is to connect two clauses using a particle like と(to) or そして(soshite), which both mean “and”.

❌昨日新しい本を買ったんだ。と、すごく面白い。
Using と like this is grammatically wrong.

❌昨日新しい本を買った。そして、すごく面白い。
Using そして like this is not grammatically wrong, but it’s not natural.

Another mistake is to use って(tte) to connect two clauses.

❌昨日新しい本を買って、すごく面白い。

って is used to connect two verbs when you do one action after another.

⭕️本ほんを買かって読よんだ。
Hon wo katte yonda.
I bought a new book and (then) read it.

Just remember to use けど, 〜んだけど, 〜んですけど, or 〜んですが when you want to bring up a subject and connect two clauses.

カメラを持もってきたんだけど、SDカードを忘わすれちゃった。
Kamera wo motte kitan dakedo, SD kaado wo wasurechatta.
I brought a camera, but I forgot the SD card.

チケットが2枚まいあるんだけど、一緒いっしょに行いかない？
Chiketto ga ni mai arun dakedo, issho ni ikanai?
I have two tickets, and… do you wanna come with me?

来週らいしゅうディズニーランドに行いくんだけど、一緒いっしょに行いかない？
Raishuu Dizuniirando ni ikun dakedo, issho ni ikanai?
I’m going to Disneyland next week… do you wanna come with me?

Using んだ to Make a Conclusion

Yet another way to use の or んだ is when you make an assumption and talk to yourself.

Maybe you’re walking around the city and see someone who seems to be lost. You can say to yourself:

迷まよっちゃったんだ。
Mayocchattan da.
(I see,) He’s lost…

* You can learn about ちゃった(chatta) in this video.

Or maybe one day, you see your friend, but he looks sad, and his eyes are wet. You can conclude:

泣ないてたんだ。
Naitetan da.
He was crying.

泣ないてる (naiteru) = is crying
泣ないてた (naiteta) = was crying

桜さくらちゃんは目めが腫はれてる…泣ないてたんだ。
Sakura-chan wa me ga hareteru… naitetan da.
Sakura’s eyes are puffy. (I see…) She was crying.

As another example, you get on the train one day and see a woman with a large belly sitting in a priority seat. You assume:

あ〜、妊娠にんしんしてるんだ。
A~, ninshin shiterunda.
Oh, (I see) she’s pregnant.

If you see your friend has earrings one day, you can say:

ピアス買かったんだ。
Piasu kattan da.
(I see) You bought earrings.

Or, if you see Misa’s room, you might say:

みさはカネキが好すきなんだ。
Misa wa Kaneki ga suki nanda.
(I see…) Misa likes Kaneki.

みさはピンクが好すきなんだ。
Misa wa pinku ga suki nanda.
(I see…) Misa likes pink.

みさ、ハワイ(に)行いったんだ。
Misa, Hawai ni ittanda.
(I see…) Misa went to Hawaii.

Using の When You’re Surprised

Yet another way to use の is when you’re surprised. Suppose you meet a new friend at a bar who says:

お酒さけ飲のめません。15歳さいなんです。
O-sake nomemasen. Juu-go sai nan desu.
I can’t drink alcohol. I’m fifteen years old.

You reply:

15歳さいなの⁉︎
Juu go-sai na no!?
15歳さいなんですか⁉︎
Juu go-sai nan desu ka!?
You’re 15 years old?!

* 歳さい (sai) is treated as a noun, so remember to add な (na).

Or maybe one day, your girlfriend says to you:

実じつは妊娠にんしんしてるんだ。
Jitsu wa ninshin shiterun da.
(Guess what…) I’m actually pregnant.

Or, if you’re a girl, you can play a prank on your boyfriend by saying the sentence above, and they’ll respond:

え⁉︎妊娠にんしんしてるの⁉︎
E!? Ninshin shiteru no!?
Huh!? You’re pregnant!?

As another example, if you’re a boy, you might be flirting with a girl at a bar when her boyfriend suddenly appears, and you say:

彼氏かれしいたの!?
Kareshi ita no!?
(Oh) You have a boyfriend!?

Or, if you’re planning to go to a bar after work, and your friend says:

友達ともだちもう一人ひとり連つれてもいい？
Tomodachi mou hitori tsurete mo ii?
Is it okay if I bring one more friend?

If you want to be sarcastic, you can say:

友達ともだちいたんだ⁉︎
Tomodachi itan da!?
(Oh) You have a friend?!

Or maybe your friend doesn’t like to go to bars, but he says he’ll go anyway. You can say:

え⁉︎行いくの⁉︎
E!? Iku no!?
Huh!? You’re going!?

You can also use の to express skepticism. For instance, if you are shopping with a friend, and she wants to buy an ugly sweater, you can say:

それ、買かうの？
Sore, kau no?
Are you really buying that?

Or, if she already bought it:

買かったの？
Katta no?
Did you really buy it?

Maybe your friend doesn’t like Pokémon, but they bought the game anyway. Surprised, you say to them:

新あたらしいポケモンのゲームを買かったの？
Atarashii Pokemon no geemu wo katta no?
Did you really buy the new Pokémon game?

If your friend watched an anime that you didn’t expect them to watch, you can say:

新あたらしいアニメを見みたの？
Atarashii anime wo mita no?
Did you really watch the new anime?/ Did you watch it? Elaborate.

If your friend hurts his ankle, but he says he can still walk, you can say:

歩あるけるの？
Arukeru no?
Can you really walk?

 

Today, we learned all these ways we can use explanatory particles:

• Place の at the end of a sentence when you want an explanation and are curious.
• Place の, 〜んだ, or 〜んです at the end of a statement when you give an explanation.
• Use 〜んだ when you want to start a conversation or change the subject.
• Use 〜んだけど, 〜んですけど, or 〜んですが to connect two clauses.
• Use 〜んだ to make a conclusion.
• Use 〜んだ to express surprise or skepticism.

That’s a lot to memorize, but if you keep practicing, it’ll start coming to you naturally. So, be sure to use の and 〜んだ by yourself, and you’ll sound more natural the next time you have a conversation in Japanese.