[Nebelherz]

Language changes all the time. Who define, what is proper English or any other language? You just see Old English is different from Modern English. But do we know, why excactly it changed this why? Maybe because, some people just started talking different? I don`t excactly know, why languages changes over time. Sure there are coming new words from other languages in one`s languages, but it`s not just that what changes over time. Some words starts to become totally different or words are used for different meanings, than their were used before. You can also see on dialects, that some words, are spoken differently and also meanings are changed or even grammar is different.

I think you does just need to learn English for Japanese, because there are more English Japanese learning materials, than in German. Ok, I think also, that English is a must, because it`s a world language.
^^; My English isn`t also very well, since I don`t use it that often to writing and speaking. (I use it more for reading. There are so many nice English books, which are not published in German. Ok anyway, I read also books in English, which are published in German, but why reading a translation, if a can have the original?)
Sure, I want to become better in English, but I don`t need too be perfect in English, for learning Japanese.