Is it possible to use のが twice in a sentence?

Question

I'm doing a project for my Japanese class and I'm trying to write the question "I enjoy learning about Japan." And the only way I can think to do that is 「私は日本を学ぶのがするのが楽しいです。」 is that possible or is there another way to say that phrase that I'm not understanding?

Answer 1

It is possible, but "I enjoy learning about Japan." is

私は日本について学ぶのがするのが楽しいです

It has really nothing to do with using のが twice. As pointed out in the comment, 学ぶ is a verb, which is nominalized by の, so that 学ぶのが means Learning (something) is.

A minor point is that generally you use better について for about.

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のが can appear twice, e.g. if you a nominalized clause. A bit contrived example is:

日本語を学ぶの¹が難しいの²が、日本人である自分にはよくわからない

I, being a Japanese, do not quite understand that learning Japanese is difficult.

の¹ works as a nominalizer for to learn (i.e., like ing) and の² as a nominalizer for the clause 日本語..難しい (i.e., that in English).

Answer 2

Rather than cascading のが onto the same clause, we can think about relativizing two clauses, each of which have a が subject marker: AがBがC, such that both of the が are applied to some verb phrase nominalized by の: AのがBのがC.

How about:

試験を合格するのが楽だったのがよかった。Shiken-o gōkaku-suru no ga raku datta no ga yokatta. (That it had been easy to pass the exam was a relief.)

In the sentence 私は日本を学ぶのがするのが楽しいです the のがするのが is just a pleonasm that shortens to のが. I.e. は日本を学ぶのが楽しいです。I don't recall having heard or read such a のが pile up, for what it's worth. Some verbosities involving the ことが nominalization are fairly often heard, like Xすることができない instead of simply Xできない, where X takes する.