speckled furnace

例句：

1. 1. The speckled furnace is a popular choice for heating homes in cold weather.
   斑点炉子是寒冷天气中加热房屋的热门选择。
2. 2. The speckled furnace was designed to improve the efficiency of the heating system.
   斑点炉子被设计用来提高供暖系统的效率。
3. 3. The speckled furnace has been used for centuries as a way to heat homes and buildings.
   斑点炉子作为一种加热房屋和建筑的方法，已经使用了好几个世纪。