hoar frost

例句：

1. 1. The hoar frost on the ground is a reminder of the cold winter weather.
   地面上的霜冻提醒着我们寒冷的冬天。
2. 2. The farmers were worried about the hoar frost affecting their crops.
   农民们担心霜冻会影响他们的庄稼。
3. 3. During the night, the temperature dropped to below freezing point, and hoar frost formed on the window panes.
   夜间，温度降到了冰点以下，窗户上的玻璃上形成了霜冻。