>私も正確な英語を学ぶ必要があるので、お互いに言葉を学べたらと思います。
>Because I need to learn correct English, <something-- This part confuses me!>
Because I, too, need to learn correct and standard English, I wish we can learn language from each other.
>伝わる英語ではなく、正確な英語を学びたいのです。
>文法的に正しいだけではなく、自然な文章を書きたいのです。
>Not only grammatically correct <English>, but also natural-sounding English.
I want to learn not "English that is barely enough to communicate," but correct English. Not just grammatically correct, I want to write natural English.
(My comment: you know, we often understand what people mean even if there are grammar mistakes and awkward usages. But he doesn't want to be satisfied by only "being able to make him understood." )
>私は日本語の英作文を添削することができます。
>I can correct <something about English and Japanese>.
I can correct (your) English composition written in Japanese.
(I guess he means "Japanese composition. " Not English! lol)
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All the rest looks good:)