necessity

/nəˈsɛsɪti/

the condition of being essential or indispensable

中文释义：必要性；必需品；必然

Clean water is a basic necessity for human survival.

清洁的水是人类生存的基本必需品。

There is a necessity to reduce carbon emissions to combat climate change.

有必要减少碳排放以应对气候变化。