Need help with のだ , んだ conjugating please


#1

I’m having trouble translating this chart showing how to conjugate noda. I think it says on the first chart in plain, it is student, it is t drink. Then negative says it is not student, it is not to drink. But I can’t tell the difference between the first chart and second chart for translating. I think it says the exact same way but spelled differently, but I’m not sure and would appreciate any help with this. This chart is from tae kim’s grammar guide here http://www.guidetojapanese.org/learn/grammar/nounparticles

     Noun/Na-Adj 	Verb/I-Adj

Plain 学生なんだ 飲むんだ
Negative 学生なんじゃない 飲むんじゃない
Past 学生なんだった 飲むんだった
Past-Neg 学生なんじゃなかった 飲むんじゃなかった

Noun/Na-Adj 	Verb/I-Adj

Plain 学生なんだ 飲むんだ
Negative 学生じゃないんだ 飲まないんだ
Past 学生だったんだ 飲んだんだ
Past-Neg 学生じゃなかったんだ 飲まなかったんだ


#2

Basically, the first chart is conjugating the noun/verb, while the second chart is conjugating the んだ ending instead (though somehow when you copied them you’ve switched the charts). Please note the next line reads “I would say that the past and past-negative forms for noun/na-adjective in the second chart are almost never used (especially with 「の」) but they are presented for completeness.”

So, basically, ignore the second chart, because noone speaks like that.


#3

Is my translation right then? Do they both say the same thing? I’m not exactly sure how to transfer this into English correctly.


#4

Well, I mean, “it is student” isn’t correct English.

If someone said 学生なんだ I would imagine that as something like “oh, he’s a student.” Because the purpose of のだ is to emphasize the explanatory element of a sentence.

Edit: obviously the “he” could be replaced with you, she, they, etc. Depending on context.