Both "warmth" and "Yi Yi" are terms for writing long-term vision, both of which mean vagueness and vagueness, but they cannot be interchanged because of "warmth".

It is impossible to see the general outline of the distant village clearly, but the building is still in the author's subjective feeling; "Yiyi" is about cooking smoke, which is higher in the sky and more visible than the village, so "Yiyi" means that cooking smoke is still visible although it is far away.