Inversão de orações com expressões como ''not only''

Hey, guys, can anyone explain to me what happen in those sentences, in which the teacher says:
Not only after the prices get lower will people buy it.
And the studant says: People will only buy it after prices get lower.

My teacher said it is a formal ways to speak, but it is mostly common in writings. But why is there a "no" in the first sentence?

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4 respostas
Ordenar por: Data
Leonardo96 19 293
It seems to me like the sentence is incomplete and requires continuation in order to make more sense:

Not only after the prices get lower will people buy it, they'll also do so regularly.

Makes more sense now, doesn't it?

Anyway, I'm not so sure if that's what you wanted to clear up, when I read the title of the thread I was pretty sure it was going to be about the modal verb being placed in the sentence like it was a question, ex: not only should you, not only can I,etc. But if you just thought it didn't make sense for that "not" to be there it's because the sentence needed to continue. It's a structure that suggests there's something else on top of what was previously mentioned:

Not only did she yell at him, she also slapped him in the face.
Not only will you get hurt if you do that, you'll be in a hospital bed for 2 weeks.
Not only … but also
Grammar > Words, sentences and clauses > Word order and focus > Not only … but also
De English Grammar Today
We use not only X but also Y in formal contexts:

The war caused not only destruction and death but also generations of hatred between the two communities.
The car not only is economical but also feels good to drive.
This investigation is not only one that is continuing and worldwide but also one that we expect to continue for quite some time.

We can sometimes leave out also:

I identified with Denzel Washington not only as an actor but as a person.

To add emphasis, we can use not only at the beginning of a clause. When we do this, we invert the subject and the verb:

Not only was it raining all day at the wedding but also the band was late.
Not only will they paint the outside of the house but also the inside.

When there is no auxiliary verb or main verb be, we use do, does, did:

Not only did she forget my birthday, but she also didn’t even apologize for forgetting it.

Source: dictionary.cambridge

Hope it helps!
Ok, I get that, but on my exemple, both sentences have different meanings, right? Because in the first exemplo is saying that "NOT ONLY after"... And the second sentence mentions "ONLY after". So, my question is, why to invert the sentence there is a "no" in one sentence, and in the other one we don't put "no"? Do both sentences have the same meaning, and I'm not seeing it, or do they really change the meaning?
Hi Bruna,

To me, the first sentence doesn't make sense. At least I've never seen that structure.
The second one is ok. However, it does not have the "inversion" idea, because it requires a modal verb, as Leonardo wrote earlier.

Take care!