遗憾的是用英语怎么说

1. It's a pity that we couldn't make it to the concert.

很遗憾我们没能去参加音乐会。

2. Unfortunately, the weather didn't cooperate for our outdoor plans.

不幸的是，天气不利于我们的户外计划。

3. Regrettably, I won't be able to attend the meeting tomorrow.

遗憾的是，我明天不能参加会议。

4. Sadly, we had to cancel our vacation due to unforeseen circumstances.

可悲的是，由于不可预见的情况，我们不得不取消了度假计划。

5. It's a shame that we missed the deadline for the project submission.

很遗憾我们错过了项目提交的截止日期。