Since I started to go to school, I have always gotten good grades. Since I started school, I have always gotten good grades.

You can also say "I have always had good grades". Gotten is used more in American and used less in the UK. So it depends who your audience is :)

During myIn elementary and middle school, there were about sixty students in a class, and I almost took placewas usually in the top three. In elementary and middle school, there were about sixty students in a class, and I was usually in the top three.

There were about 70-80 percent of the opportunities were for for the top one. 70-80 percent of the opportunities were for for the top one.

I hope I have understood what you meant here.

Many years later, I realized that itI was totally wrong doing this, so I decided to learn again, but what can I learn at my age? Many years later, I realized that I was totally wrong doing this, so I decided to learn again, but what can I learn at my age?

After I thoughtthinking about it manyfor a long times, I decided to learn a foreign language. After thinking about it for a long time, I decided to learn a foreign language.

Maybe that wais is the only thing and themost suitable thing I could do. Maybe this is the most suitable thing I could do.

After learning it for more than onea year, I felt like it was not a bad thing. After learning it for more than a year, I felt like it was not a bad thing.