I Study/Am Studying English?

Hello Teachers

I have a question. The question is: why “I am now studying English in school” is more natural than “I study now English in school” ?

This question came originally from a Japanese guy (probably an English teacher) whom I had an online talk with on the usage of the verb “study”. I told him that sentences like “I study English everyday” or “Most of the Japanese kids study English in school” are natural, but “I study now English in school” is not. And I added we have to say rather “I am now studying English in school”. Then he asked me the question above.

I believe this question is of beginner’s levels, but I myself could not find a persuasive answer to it. What I told him as the reason was only that English speakers take a personal activity of studying a language as a short-term event that will eventually ends, and it is a rule of English that they use a present progressive construct rather than a simple present construct for such short-term events. But he seems not to have got satisfied with this answer. So could you give me any better answer?

paco