necessity

Water is a basic necessity of life.

水是一种基本生活必需品。

Travel has become a necessity.

旅行已经成为一种必需品。

As soon as the necessity for action is over the troops must be withdrawn.

一旦军事行动的必要性不复存在，部队必须撤离。

The fund-raising ability is largely a product of experience and necessity.

筹集资金的能力在很大程度上是经验和必要性的产物。

Andrew Schubert, a researcher at the institute for science policy research, says that the rising collaboration is partly out of necessity.

科学政策研究所的研究员安德鲁·舒伯特表示，这种日益增强的合作在一定程度上是必要的。

The president pleaded that strong rule from the centre was a necessity.

总统争辩说来自中央的强有力的统治是一种必然。

Living in London, he felt, was an unfortunate necessity.

他觉得在伦敦生活是迫于无奈。