"It's cold at home" 是表达家里很冷的常用英文表达方式。"Cold" 是形容词，指的是温度低的状态。"At home" 是副词，指的是在家里的地方。
例句：
It's cold in here. Can you turn up the heat? (这里很冷。你能调高一点温度吗？)
I'm freezing. Can you close the window? (我很冷。你能把窗户关上吗？)
The house is so cold. I think the furnace isn't working. (房子好冷。我想炉子坏了。)
注意，在英语中，"cold" 还有其他用法，比如形容食物、气候、情感等。例如：
The soup is cold. (汤很冷。)
It's a cold day. (今天很冷。)
She gave him a cold stare. (她冷冷地看着他。)