Constant variations in the amount of sunlight available on Earth at any given location make energy storage a necessary design feature of terrestrial solar-energy systems.
在地球上任何一个特定地点，阳光的不断变化使能量储存成为地球太阳能系统的一个必要设计特征。
2
Maintenance for a given body design of an organism is relatively constant.
对一个有机体特定主体设计的维持是相对恒定的。
3
This introduces the one constant in software analysis and design: change.