The origins of my interest in the Japanese language is something that natives often ask about, but I'm always having trouble with the grammar for answering that and want to rest this case once and for all.
For example, I might want to say that I've had an interest in the Japanese culture since middle school, and therefore have been studying Japanese for quite a while. My first attempt would be:
中学の頃から日本の文化に興味を持っていたことはあるので、日本語の勉強はずいぶん前からやったことがあります。
However, that feels grammatically a bit off and I'm not quite sure how to make it better. What's the problem here?
Another common case is this; Originally I started studying Japanese to be able to play games in it, and I've been studying for five years now. What I'd say from the top of my head is the following:
もともとはゲームを日本語にやれるために日本語の勉強を始めたんだが、もう五年間を勉強したことはあります。
This is probably alright in a conversation, but I don't really know which word to use for playing games, the 始めたんだ seems slightly incorrect in this context, and I have no idea whether the part after the comma is proper Japanese or not. It seems a bit repetitive at any rate. As I don't want to have any doubt in the vocabulary or sentence structures I'm using, I would like to know which parts should be corrected, if any?
I'm also not entirely sure whether this type of question is allowed here or if it's too broad, so let me know about that as well.
Thank you so much!