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with trouble; at great pains
rare; valuable; precious; long-awaited
kind; generous
specially; especially; expressly
せっかくですからいただきます。
Since you went to the trouble, I will have some.
せっかくの休みを無駄にする。
I waste my precious day off.
せっかくの旅行を楽しもう。
Let's enjoy the trip we went out of our way for.