Okay, my bad, upon checking it appears my Japanese really is rusty. ~てからでなければ does exist (although I found literally 0 instances of it on sites like alc.co.jp, which is really weird) and it's supposed to mean "If I don't first <verb>". So in this case, "if I don't first get up at 4, I won't make it to the airport on time."
At any rate, it looks like an unnecessarily contrived way of just saying なければ and the kind of nuance you wouldn't be asked to know about for N3, but what do you guys think? What's the right answer?
It's definitely not the most commonly used grammar structure, at least. It makes sense post-analysis, but I doubt I would have come up with it in abstraction compared to other alternatives to confer a similar meaning. It's definitely interesting to see. It would probably be more important for N2 and above, but I have no clue.
Speaking of things Genki does and does not do, I find Genki book I is terrible at explaining the difference of はand が. I don't know if the later books somehow do it better, but does anyone have recommendations for some reading material that better covers the difference in nuance between these particles?
Honestly, I felt it was one of those things that doesn't really have a satisfactory equivalent in English that makes it easier to wrap one's head around, but experience definitely helps make it more of a...concrete idea in one's mind.
One useful point to know, in my opinion, is noting how it emphasizes different things in a sentence.
The topic marker は places an emphasis on the action (or whatever follows the topic).
The subject marker が places the emphasis on the subject that precedes the particle.
This is evident in questions like,
だれがXを食べましたか。
The focus is on wanting to know
who ate X, rather than focusing on the actual act itself.
Or for a more comparative example:
A)（山本さんは）本を読みました。
Which would be a response to a question like:
Q) 山本さん
は何をしましたか。
We are interested in knowing what Yamamoto-san was
doing. (And as you know, what follows is not limited to an action.)
vs.
A) 山本さんが（あの）本を読みました。
As a response to:
Q) 誰
が（あの）本を読みました。
We want to know the
subject who performed the act in question.
That's at least a helpful foundation to start from, in my opinion before one starts to delve into nuances and the other uses for the particles in question. But, of course, it is not that simple. Sometimes the subject and the topic of a sentence are identical. The topic of a sentence is, in most cases, contextual (and therefore dropped since it is implied).
Learning things like giving/receiving and causative/passive in terms of grammar helps distinguish the two later on. So just bear with it for now. It will feel more organic before you know it.
