rhythm

noun [抽象名词]（声音或运动的）节奏，韵律，节拍；节奏感；规则变化，节律；（艺术作品的）匀称，和谐；（韵文或散文）抑扬节奏

A rhythm is a regular pattern of changes, for example changes in your body, in the seasons, or in the tides. (
身体、季节等的) 规律性变化