Correção de texto de uma amiga

Minha amiga me pediu para postar o texto dela, se puderem me ajudar a corrigir, agradeço.

Hello. I am sixteen-year-old girl. I have studied American English since two hundred eleven or thirteen, but unfortunately, I still make many mistakes. Becoming fluent in English is not my dream, but it would help me a lot. Sometimes I have serious problems with plural forms, adverbs, and the order of some words. I cannot surrender and be weak against these problems, which were already mentioned, I can face all of them without the help of people. There is nothing left to be done by me, unless studying and studying without any time for breathing or even living. Studying English may be an obsession, but it could be a worthy way of living without any life too. I am not tired enough to be stopping yet.
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Algumas observações:

Hello. I am a sixteen-year-old girl. ( precisa acrescentar o artigo "A" porque a expressão "sixteen-year-old " está adjetivada, é uma característica da menina.)

I have been studying (aqui o presente perfeito contínuo é uma melhor opção, pois ela ainda continua estudando, é uma ação que começou no passado e ainda não terminou) American English since two hundred eleven or thirteen, (2011 Twenty eleven ou two thousand eleven) but unfortunately, I still making (não gosto de usar a expressão sempre e nunca, mas acho que podemos dizer que após "still" o verbo sempre deve estar no gerundio) many mistakes. Becoming fluent in English is not my dream, but it would help me a lot.

Sometimes I have serious problems with plural forms, adverbs, and word order (É mais simples)
I cannot surrender and be weak on these problems ( weak against ... Pra mim não faz sentido.) which were already mentioned, I can face all of them without people's help. (eu particularmente gosto de receber ajuda)

There is nothing left to be done by me, unless studying and studying without any time for breathing or even living. (caramba, deve ser difícil)

Studying English may be an obsession, but it could be a worthy way of living. (without any life too... Não entendi muito bem o sentido) I am not tired enough to be stopped.

Bem, como disse no início são apenas algumas observações, espero que o texto ganhe mais dicas.)

Boa sorte pra você e pra sua amiga.
Avatar do usuário gian2hard 2270 1 7 50
Friendly correction, " I still making many mistake " is wrong.

"I'm still making many mistakes" is correct.
"I still make many mistakes" is also correct.

"I still make many mistakes" conveys pretty much the same meaning as "I'm still making many mistakes", but its shorter and sounds better.