803 - のだ ([explanation])
のだ, as well as it's other forms (e.g. のです、んです、んだ、etc.), is an elusive concept to grasp. That's why we talk about it in so many of our lessons.
One of the first places we mentioned it was in our Bunkai Beast grammar course:
- Feminine の
- Intro to んだ
I recommend reading those two lessons, if you haven't already.
This article of ours also touches on this topic: How to Say “So I was thinking…” in Japanese.
Even if you read all of these different explanations, however, you may still find that it's hard for you to use のだ naturally in your own Japanese.
You are not alone. I still find myself wondering whether or not I should be using it in certain sentences.
The problem is that in English we do not indicate explanations are being made in quite the same way.
Consider the following:
#1: I'm saving 150,000 yen every month. I want to buy my parents a house someday.
#2: I'm saving 150,000 yen every month because I want to buy my parents a house someday.
In #1, above, it is clear that the reason the speaker is saving money is because he wants to buy his parents a house someday. He does not need to explicit say "because" for this to be clear.
In #2, "I want to buy my parents a house someday" is explicitly stated as the reason the speaker is saving money. This is done by including the word "because." Accordingly, the nuance changes a bit.
The combination of sentences we have in #1 is coming pretty close to how のだ is used in Japanese. Specifically, a Japanese person would say something like this:
I'm saving 150,000 yen every month. I want to buy my parents a house someday のだ.
Putting that のだ onto the end of the explanatory sentence makes it clear that this information is being included for some reason.
Let's see this example in Japanese. We're using formal language, so we'll say のです in this case (not のだ):
まいつき じゅうご まん えん を ちょきん しています。 いつか りょうしん に いえ を かって あげたい のです。
I’m saving 150,000 yen every month. I want to buy my parents a house someday.
Literally: “every month + 150,000 yen + を + saving (money) + am doing. + someday + (both) parents + に + house + を + buy (and) + want to give (them) + のです.”
To recap: のだ is used when explaining a situation or the reason for something.
Let's look at how to use it in sentences...
👷 Construction 👷
This is fairly simple:
Plain Form Word ＋ のだ
na-adjective / NOUN ＋ なのだ
Keep in mind that のだ may appear in other forms: んだ、のです、んです、のである、etc.
ピーナッツ は いれないで ください。 アレルギー なんです。
Please don’t put any peanuts in it. I’m allergic.
Literally: “peanuts + は + don’t insert (and) + please. + allergy + なんです.”
↑ "I'm allergic" is the reason the speaker doesn't want the listener to include any peanuts.
きょう の ランチ も ツナマヨ おにぎり？ ほんと に だいすきなんだ ね。
You’re having tuna-mayo onigiri for lunch again? You really love those things, don’t you?
Literally: “today + の + lunch + も + tuna mayo + onigiri (=rice ball)? + truly + loved / greatly liked + なんだ + ね.”
↑ "You really love those things" is the (inferred) reason that the listener is eating them for lunch so often.
By the way, even if you typically dislike mayo, you should try it out when you're in Japan. It tastes quite different than the mayo in the US, for example.
If you're going to try it, might as well go for the tuna-mayo onigiri:
アメリカじん は スーパー にも くるま で いく。 アメリカ は くるましゃかい なのである。
In the US, people even drive to the grocery store. It is a car-based society.
Literally: “American (person) + は + supermarket + に + も + car + で + go. + America + は + automobile society + なのである.”
Note: である is used more often in written language than in spoken language.
↑ "[The US] is a car-based society" is the reason that people there even drive to the supermarket.
Ready to level up?
Negative forms like のではありません and んじゃない are used when partly negating something.
In other words, you can use them when clearing up a misunderstanding:
この ぼうし は もらった のではありません。
No one gave me this hat.
Literally: “this + hat + は + received + のではありません.”
↑ Maybe the listener (wrongly) assumed that the speaker received the hat from someone. Perhaps the speaker does own the hat, but it wasn't a gift. As such, she might choose to further clear up the misunderstanding by adding a sentence like:
じぶん で かった のです。
I bought it myself.
Literally: “by myself (=oneself + で) + bought + のです.”
この ぼうし は もらった のではありません。 じぶん で かった のです。
No one gave me this hat. I bought it myself.
Literally: “this + hat + は + received + のではありません. + by myself (=oneself + で) + bought + のです.”
↑ "I received this hat from someone" is not entirely correct. "I bought this hat myself" is why I have it now.
Let's look at a similar situation. んじゃない is used to clear up a misunderstanding. んだ is then used to further explain the circumstances of a situation...
おとうさん の パソコン で あそんじゃ いけない って いった だろう。
Didn’t I tell you not to play with my computer?
Literally: “dad / father + の + PC + で + must not play + って + said + だろう.”
Note: The English translation is a rhetorical question.
ぼく が やった んじゃない よ。 てっぺい が やった んだ。
I didn’t do it. It was Teppei.
Literally: “I + が + did + んじゃない + よ. + Teppei + が + did + んだ.”
Reading lessons on のだ might not be too terribly confusing... but using it naturally in your own spoken Japanese is quite a challenge.
The best advice I can give is to be patient and pay extra attention to how Japanese people are doing it. If you can find a Japanese person to correct you when you use it incorrectly (or forget to use it), then... well, thank them for being awesome.