out of the clear blue sky
成語所屬單字sky
out of the clear blue sky — 慣用語
1. completely unexpected; happening suddenly without any warning
1.慣用語
釋義
突然；毫無預警地；晴天霹靂
completely unexpected; happening suddenly without any warning
例句
The job offer arrived out of the clear blue sky while she was still looking for work.
Ayesha received a letter from an old friend out of the clear blue sky after ten years.