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although; despite; even though; and yet
whereas; while
if only; I wish
in order to
約束したのに来なかった。
Even though we made a promise, you did not come.
せっかく作ったのに食べない。
Even though I made it specially, you will not eat it.
知っているのに教えてくれないんです。
Even though you know, you will not tell me.