故宫的采暖方法以地炕火道为主，以炉火为辅。

Heating method of the the Imperial Palace is pit fire, with the fire auxiliary.

youdao

“在那个洞里，”他自言自语道，“一定有火。”

"In that cave," he said to himself, "there must be a fire."

youdao

“在那个洞里，”他自言自语道，“一定有火。”

"In that cave," he said to himself, "there must be a fire."

youdao