complement each other; supplement each other ❍ 没有这种行政命令，社会秩序就无法维持，这是人们的常识所了解的。这同用说服教育的方法去解决人民内部的矛盾，是～的两个方面。(《毛泽东选集》 Ⅴ—369) It is common sense that without them the maintenance of public order would be impossible. Administrative regulations and the method of persuasion and education complement each other in resolving contradictions among the people.
相辅相成
complement (or supplement) each other ～的经济结构complementary economic structure
相辅相成xiānɡ fǔ xiānɡ chénɡ
辅：辅助。形容两件事物相互辅助，相互促成。complement each other, supplement each other, be inseparably interconnected