节能是永恒的主题，尤其在当今世界已成为热门课题。

Energy-saving is eternal theme, so in today's world it has become a hot topic.

youdao

节能是永恒的主题，尤其在当今世界已成为热门课题。

Energy-saving is eternal theme, so in today's world it has become a hot topic.

youdao