cold thickening

例句：

1. 1. The cold air made the ground feel like it was freezing.
   寒冷的空气让地面感觉像是在结冰。
2. 2. The ice-up on the river has caused a lot of problems for the fishermen.
   河面上的冰层给渔民们带来了很多麻烦。
3. 3. During winter, we often see people walking around with their hands in their pockets to keep warm.
   冬天，我们经常看到人们把手插在口袋里以保持温暖。