N3
折角
せっかく
With trouble, At great pains, Take the trouble, Might as well..., Rare/long-awaited occasion
せっかく休みを取ったのに雨が降ったから予定が台無しだ。
I went through the trouble to get a day off, but it rained, so my plans were ruined.
Explanation
「折角」 has 2 uses
1Make the most of it
A chance or kindness is precious, so use it well, often with 「〜から」 or 「〜なら」: 「せっかくだから、食べていこう」.
折角の友達との遠足だから、たくさん遊びたい。
Since this trip with friends is a rare occasion, I want to have a lot of fun.
折角大学を卒業したんだから、いい会社で働くつもりだ。
Now that I've finally graduated from university, I plan to work for a good company.
2All for nothing
Something hard-won goes to waste, often with 「〜のに」: 「せっかく作ったのに、誰も食べない」.
折角この旅行の準備をしてきたのに....
Despite going through all the trouble to finish preparations for the trip...
せっかく休みを取ったのに雨が降ったから予定が台無しだ。
I went through the trouble to get a day off, but it rained, so my plans were ruined.