necessity

1. N-UNCOUNT The necessity of something is the fact that it must happen or exist. 必要性

There is agreement on the necessity of reforms. 關(guān)于改革的必要性有一致意見。

As soon as the necessity for action is over the troops must be withdrawn. 一旦軍事行動的必要性不復存在，部隊必須撤離。

2. PHRASE If you say that something is of necessity the case, you mean that it is the case because nothing else is possible or practical under the circumstances. 勢必[正式]

...large families where children, of necessity, shared a bed. …孩子們必定共睡一張床的大型家庭。

3. N-COUNT A necessity is something that you must have in order to live properly or do something. 必需品

Water is a basic necessity of life. 水是一種基本生活必需品。

4. N-COUNT A situation or action that is a necessity is necessary and cannot be avoided. 不可避免

The president pleaded that strong rule from the centre was a necessity. 總統(tǒng)爭辯說來自中央的強有力的統(tǒng)治是一種必然。