Supplement each other

xiāng fǔ xiāng chéng

Explanation: auxiliary. It means that two things cooperate with each other, assist each other, and both are indispensable.

Source: Zhang Dai's "Almanac Eye Preface" of Ming Dynasty: "Those who predict the sun and those who predict fate must complement each other; then the two will be unobstructed."

Structural combination Formula

Usage is often used to refer to the interdependence of two aspects of things. Generally used as predicate and attributive.

Correct pronunciation and appearance; cannot be pronounced as "xiànɡ".

Distinguish the form and assist; it cannot be written as "catching".

Synonyms complement each other and opposites complement each other

Example sentence Rich knowledge and a healthy body are the basis for career success; both ~; one is indispensable; both must receive sufficient attention.