a windless day的用法和样例：
- Mr Heeks, a student, used a macro camera to get in close and had to wait patiently for a windless day.
- When the sea is calm on a windless day, it looks like a smooth mirror merging with the sky on the distant horizon and such a sight is named The Azure Sea Stretching Ten Thousand Miles.
- You shouldn't be that tired after a windless night.
- “The board will be as wide and sturdy as our conference table, we'll do it on a windless day, and I'll pay $1,000 cash on the spot.
- Don't ignore the Star-scatterred sky in a windless night.