日本語をクリックすると英文が表示されます。まずは自分で英語にしてから答え合わせを。
I truly wish I could help, but...
It's a generous offer, but I must decline.
Sadly, I can't stretch myself that far.
Let's just say it wasn't meant to be this time.
For various reasons, I have to decline this time.
If I had more room, I'd have taken it on.
I'm glad you asked, but I have other plans.
Unfortunately, that's outside my expertise.
Sorry, but I don't think I can help this time.
It pains me, but I'll have to pass this time.
I'd love to, but it looks difficult.
I'm afraid I can't take responsibility that far.