朝ごはんを食べるんじゃなかった？

I think this is a weird sentence (in any language).

Maybe context will help..

ボブ：今日は朝ご飯を全部食べた。
アリス：(今日は)朝ご飯を全部食べるんじゃなかった。今朝はパーティだから。

So, I think it could be a kind of "didn't eat breakfast" if you change the context a bit.

Though, I see it more as, "it wasn't that I eat breakfast."

サッリー：ジムのところで朝ごはんを食べたの？
アリス：朝ごはんを食べるんじゃなかった。

Or even "its not something to be eaten."

どうして朝ご飯を食べたの？朝ご飯をたべるのじゃなかった。


Wait! That's what the page says. lol. Follow the more literal translation he gives. They are closer to what's really being said. Did I mention this is a weird sentence?

"Didn't eat breakfast"

Would more likely be 朝ご飯を食べなかった(の)

It's used a ton, by parents to their children or by in quarrels. A classic one being "笑うんじゃねえ！".

Thanks for the response guys! I'm still a tiny bit confused though..

kazelee wrote:

"Didn't eat breakfast"

Would more likely be 朝ご飯を食べなかった(の)

朝ご飯を食べなかった(の) is exactly how I read it.

So what's the difference? Tae Kim says you can conjugate the verb then add のだ or conjugate the だ part of the のだ, implying they have the same meaning. Is this not the case?!

First listen to kazelee; the example sentence is a strange one. (And the overall explanation of の from that page runs together a few things that probably should be kept separate, but that is another matter. The uses of の introduced are completely unrelated, and presenting them together might make someone think they are related).

Remember that Japanese does not have a past tense; it has a completed tense. Or at least thinking that way helps unravel some of these things. Think about the state of completion

If you negatively complete the action and then add の, it is more likely to be an explanation of something with the reason being that you did not eat, as if you are explaining why you are hungry now. If you do not  complete it and then add の　and then make it negative and completed then you are saying that back then when faced with breakfast, it was something better to not do.

だって食べなかったの．which means 食べてない だから　something.
食べる（こと）は　なかった．which means  （at that time） 食べない　方　が　いい．

Side note: If you run into a particular sentence that sounds strange to you, sometimes you have to step back and see that there is no sentence said in any language that is completely determined and translatable . Every sentence comes in the context of an overall conversation, and every conversation comes within the context of a complete language structure. Sometimes you have to step away and realize that you just don't get it. No one does without a number of examples to learn from. This example is a tough one; and that whole page seems specifically designed to throw a bunch of ideas at you at once. Remember that language is like nothing else; the only way to truly explain a language is by using that very language. You can get an idea of the shape of the house, but until you walk inside the house, you cannot be sure what is in there.

This is one of the most difficult things in Japanese grammar, at least if you are including production.  As far as understanding, you often don't even need to understand the exact purpose of のだ to understand the sentence, but I think you can deal with a large majority of the cases as providing or asking for an explanation of something, or stating some assumed fact (or asking for verification of an assumed fact).

A previous poster explained this as dropping こと, but this cannot be correct because you have something like 先生なのだ (it's because he is a teacher [e.g.]) whereas *先生なのことだ is ungrammatical.  In many (perhaps most) instances of the のだ construction, inserting こと either makes the sentence ungrammatical or changes the meaning.

JSL has some good examples of this, here are a few dialogues from the book (it should be pointed out first that のだ is rare in speech, んだ is much more common, even in polite/formal speech.)
A: 今日は一日ですね！
B: いいえ、三十一日ですよ。
A: 水曜日じゃないんですか？
B: 火曜日でしょう？
A: あ、そうでしたねえ！だめですねえー私。
The use of じゃないんですか？ in the third line is like "You mean it's not Wednesday?"  In this case the "explanation" is that the reason she thought it was the 1st is that she thought it was Wednesday.  So the のだ construction will not always be explicitly providing a reason (note that you could not use から here).

A: 今何時ですか？
B: すみません。時計ないんです...
In this case the ないんです marks "I don't have a watch" as an explanation for why he's not going to tell the person the time.  Sometimes のだ is also described as stating some shared knowledge, in this case it's assumed that he would say the time if he had a watch, so saying "I don't have a watch" is enough without further comment.

(B is a cab driver, A is a foreigner)
A: 東京駅まで行ってください。
B: 日本語お上手ですねえ。日本は長いんですか？
A: いいえ。明日で、ちょうど六週間になるんですけど...
B: へえ。六週間？六週間で、そんなに上手になるんですか？
A: いえ、向こうでちょっと勉強してきたんです。
B: やっぱりねえ。
The cab driver's 長いんですか? means something like "Is it because you've been in Japan a long time that your Japanese is so good?"  A's response has the のだ in it as well (often a question with のだ can be answered with のだ).  You can also understand A's response as something like "The fact is that..."  Then the cab driver's になるんですか？ isn't really an explanation, it's more like "Is it really the case that..."  A's second response of してきたんです is an explanation "It's that I studied abroad before coming here."

Sometimes から can be substituted for のだ, sometimes it cannot.  In the last dialogue above, the 長いんですか could be 長いからですか to emphasize and strengthen the "because" aspect, but the response could not be 六週間になるからですけど because there she's not saying "It's because..." but just "The fact is that..."

Luckily, you can find lots and lots of examples of のだ in the wild because it's an extremely frequent construction, especially in speech.  Unfortunately, you'll probably never understand it completely.

Last edited by yudantaiteki (2010 January 04, 5:37 pm)