Como dizer "Marrento" em inglês

I believe the words narrow-minded, hard-headed or stubborn are appropriate.

(1) traducao-de-harshing-my-mellow-t40372.html
(2) como-dizer-teimoso-em-ingles-t4446.html
(3) como-dizer-marrenta-em-ingles-t42031.html

Stuck-up / cocky
- Convencido

(1) como-dizer-convencido-esnobe-em-ingles-t353.html

Condescending
- Ter (o ar de superioridade); sentir-se superior a alguém.

(2) como-dizer-ar-de-superioridade-em-ingles-t38918.html

EXAMPLE:

I can be very difficult to deal with.
Posso ser muito difícil de lidar.

The Portuguese word marrento(a) is quite generic, especially in our culture.
Anyway I'd like to make one more note. Please, excuse me.

Impertinent / haughty / insolent
- Impertinente; insolente; atrevido.
[weaknesses = pontos fracos]

Bold
- Ousado; corajoso.
[positive aspects = aspectos positivos]

You should read:
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She is stubborn as a mule, completely hard-headed.
Ela é teimosa como uma mula, muito marrenta.

Sometimes someone can even be a good person, but the overall impression is that the said person is given to give others a hard time.

Let´s deal with the sentence "Ela é uma pessoa difícil de lidar, muito marrenta."

Could be that the speaker mean that she is has an overbearing personality (think of what many think of Trump, Bush, etc - just saying, only for illustration´s sake). Or we could express that by stating that she has a patronizing attitude towards someone, people etc/she has a patronizing character/...a patronizing way of answering one´s questions. And so on and on...

In a very colloquial or informal way (sometimes even impolite) we could say that she has an "I don´t give a damn attitude"! Or that she always gets things her way.
There are several possibilities...

You should read:
Cf.: (1) como-dizer-cara-amarrada-em-ingles-t1670.html
(2) como-dizer-o-coracao-fala-mais-alto-em- ... 16944.html

Cocksure
adjective
- confident in an excessive or arrogant way.
PT: (confiante de mais de um jeito arrogante).

Ex.: He is the cocksure golf prodigy from California.
Ele é o prodígio convencido do golfe que veio da Califórnia.
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Brazen
adjective
- imprudent or shameless.
PT: (descarado).

Ex.: He went about his illegal business with a brazen assurance.
Ele continuou com seu negócio ilegal com uma segurança descarada.

If you describe a person or their behavior as brazen, you mean that they are very bold and do not care what other people think about them or their behavior.

_
Ballsy
adjective [informal] (US)
- determined and courageous.
PT: (maluco(a); doido(a); legal; corajoso(a); ousado(a); impetuoso(a)).
PT: (da hora; maneiro) [gíria].

A bold person is not necessarily someone who enjoys taking risks or displays how incridible he / she is. In this case, we use the adjective ballsy, which also describes the act of something which is dangerous or forbidden. The word balls is used as a slang for courage.

Ex.: She was a cool, ballsy woman.
Ela era uma mulher legal, muito doida / impetuosa.
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EXAMPLES:

"Ele não disse oi, apenas fez um aceno de leve com a cabeça. Seu jeito marrento tentando disfarçar seu desconforto."

1st Interpretation: He didn't say hello, just nodded lightly. He was trying to disguise his disconfort with ballsiness. [negative aspect].
2nd Interpretation: He didn't say hi, just wave his head quietly. It was his pride in place of the awkwardness. [positive / negative aspect].

Nouns:
Ballsiness (informal) = atrevimento; ousadia.
Pride = orgulho.
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"Ele estufou o peito e fechou a cara. Seu jeito marrento falando mais alto."

1st Interpretation: He stuck his breath out and pulled a long face. It was his pride speaking louder.
2nd Interpretation: He stepped up and sulked. His stubbornness prevailed. / He was such a hard-headed as always.

Noun:
Stubbornness = Teimosia

Phrasal Verb:
Estufar o peito:

Literal meanings:
(1) [To stick out one's chest]
(2) [To puff out one's chest]

Figurative meanings:
(1) [To step up]
(2) [To hold one's breath]
similar context: (3) [To stand out]: posicionar-se contra; fazer-se notar (destacar-se)
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REFERENCES:
(1) Collins Online Dictionary.
(2) HEACOCK, Paul. Cambridge Dictionary of American Idioms. 2003.
(3) AMMER, Christine. The American Heritage Dictionary. Houghton Mifflin Harcourt Publishing Company. 2003.