a cold frosty day的用法和样例：
- On a cold, frosty day an Ant was dragging out some of the corn which he had laid up in the summer-time, to dry it.
- It's a cold day when I missed the train.
- Relatively it's a cold day today.
- I hung out the washing to dry on a frosty day and when I went to take it in it was as stiff as a board.
- This strain of wheat can grow during a cold spring.