非常冷用英语可以说为 "extremely cold"。这个说法来源于英语中 "extremely" 这个词，意思是 "极度地"，而 "cold" 意思是 "冷"。

例句：

It is extremely cold outside today. (今天外面非常冷。)

The room was extremely cold, so I turned on the heater. (房间里非常冷，所以我打开了暖气。)

The water in the lake was extremely cold, so we didn't go swimming. (湖里的水非常冷，所以我们没有去游泳。)