Please tell me a way to solve this problem.

Since he's not coming, there's no choice but to wait.

Please tell me the method to solve this problem.

Since it's raining, it can't be helped, let's cancel today's picnic.

It's a pity that his talent is going to waste.

Since it's raining, there's nothing we can do about it.

Regrettably, his proposal was rejected.

Alas, his plan ended in failure.