Exercício: Onde está o erro das seguintes frases?

Boa tarde pessoal, irei fazer uma prova amanhã e peguei alguns modelos de provas. Uma das questões consiste em achar o erro na frase, irei botar elas em itálico, e quem puder me ajudar, ta valendo.

1- Yet in the years since the late 1980s, gyrating oil prices -- with the exception of a brief spike during the Gulf War -- have become a thing of the past.
2- the fences at either sides were five feet high and there was a wall at a the far end.
3- ... And beauty of human nature, and is consistent with the overdevelopment of one power at the expense of the rest.
4- ... No longer possible to deny his guilt. Under this system, it is said, many criminals are acquited.
5- ... Used to this to care. He helped himself to a piece of toast
6- I leaned a polite elbow on the counter and looked across at...
7- ... It may be that with experience a person learns to interpret, very rapidly, what we observes, or to draw inferences, or to do something based on deduction or induction from those observances and his past experience.


Tem mais frases, mas vou começar com essas. Se precisarem do contexto, eu escrevo o texto todo. Obrigado
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Avatar do usuário PPAULO 40635 6 32 709
Here goes my first educated guess; beginning from the end, as can you see :
7- ... It may be that with experience a person learns to interpret, very rapidly, what we observes, or to draw inferences, or to do something based on deduction or induction from those observances and his
past experience.

7- ... It may be that with experience, a person learns to interpret very rapidly what he observes or draw inferences. Or do something based on deduction or induction from those observations and his past experience.

To my thinking, in the beginning some commas were out of place, making the text be read with "hiccups", it would seem like a stop-and-go road (think of the endless stop-and-go of BR-101 roadway...). So, I made some corrections of my own, at my own risk!
Anyway, others are free to comment on or make follow-up corrections.
Avatar do usuário PPAULO 40635 6 32 709
As a matter of clarity, as opposed to ambiguity, it begins with " a person learns to interpret"; subsequently it would be expected that "a person" (or "one/someone", etc) be mentioned as "he". Hence my first little correction there.
The other changes I will leave for you to spot.
Avatar do usuário PPAULO 40635 6 32 709
6- I leaned a polite elbow on the counter and looked across at...

I think the expected correction was that one would change it to "I placed/put/rest the elbows on the table" (not the counter) as they say when talking about
Table manners.
But then grammatically speaking, it could be possible to see someone at a pub/bar that "leaned a polite elbow on the counter". By some stretch, since again, one could see "the mistake" as being the fact of "leaning a polite elbow on the counter" (good-manner-wise perhaps a no no here).

So, there is something wrong, but then it´s not. Depends on how you see it!
Well, it´s me here, others might see it differently.
Avatar do usuário PPAULO 40635 6 32 709
1- Yet in the years since the late 1980s, fluctuation oil prices -- with the exception of a brief spike during the Gulf War -- has become a thing of the past.
Avatar do usuário Telma Regina 22805 9 58 572
See my corrections below:

1- Yet in the years since the late 1980s, gyrating oil prices -- with the exception of a brief spike during the Gulf War -- has become a thing of the past.

2- the fences at either sides were five feet high and there was a wall at the far end.

3- ... And beauty of human nature, and is consistent with the overdevelopment of power at the expense of the rest.

4- ... No longer possible to deny his guilt. Under this system, it is said, many criminals were acquited.

5- ... Used to this to care. He helped himself to a piece of toast. (There are no mistakes in this phrase)

6- I leaned an elbow politely on the counter and looked across at...

7- ... It may be that with experience a person learns to interpret, very rapidly, what he observes, or to draw inferences, or to do something based on deduction or induction from those observations, and his past experience.