It depends on what weyou mean by studying. It depends on what you mean by studying.

I feel like this is a more natural way to phrase the sentence, although the way you put it wasn't wrong.

I've had tho take English subject since my third grade of elementary school. I've had to take English since third grade.

But it wasn't as though I wouldas actively learning the language. But it wasn't as though I was actively learning the language.

We mostly learned grammar, so I wasn't much able to use the language much. We mostly learned grammar, so I wasn't able to use the language much.

I think that was the breaking point when I started actively practicing. I think that was the point when I started actively practicing.

A "breaking point" has more of a negative connotation and is more used to describe the point in which everything becomes chaotic.

The biggest struggle occurred just before the breaking point in the first gradeyear of secondary school. The biggest struggle occurred just before the first year of secondary school.

I have'd never been so frustrated about learning English. I'd never been so frustrated about learning English.

At that point, it washad been several years since I had started learning it at school, and yet, my abilities were so low. At that point, it had been several years since I had started learning it at school, and yet my abilities were so low.

As I began using English substantially more, my skills quickly improved quickly. As I began using English more, my skills quickly improved.

Currently, I still struggle with my active knowledgeEnglish output. Currently, I still struggle with my English output.

I can easily understand complex sentences with rich vocabulary, but I am unable to write thesem myself. I can easily understand complex sentences with rich vocabulary, but I am unable to write them myself.

"I am" is often said/written as "I'm".