urgently needed; absolutely necessary同义词：criticalperforming an essential function in the living body同义词：life-sustainingfull of spirit同义词：full of life, livelymanifesting or characteristic of life
例句：
The government saw the introduction of new technology as vital.政府认为引进新技术至关重要。The heart is a vital organ.心脏是维持生命必须的器官。This matter is of vital importance to us.这件事对我们来说至关重要。She's a very vital sort of person.她是个精力旺盛的人。It is vital that we move quickly.我们必须快速离开。This point is vital to my argument.这一点对我的论据极为重要。The leader's vital and cheerful manner filled his men with courage.指挥官朝气蓬勃和欢欣愉悦的神态使士兵们勇气倍增。
详细解释：
vi.taladj.（形容词）Of, relating to, or characteristic of life.See Synonyms at living 生命的：属于、关于生命的或有生命特点的参见 livingNecessary to the continuation of life; life-sustaining:生命延续所必需的；维持生命的：例句：a vital organ; vital nutrients.维持生命的器官；生命所需的营养Full of life; animated:有生命的，生机勃勃的：充满生命力的；有生机的：例句：.The population of the teeming, vital slum . . . declined.(Rick Hampson).拥挤而又充满生机的贫民区的人口减少了.(理查德·汉普森)Imparting life or animation; invigorating:有生气的：增强生命力或活力的；精力充沛的：例句：the sun`s vital rays.太阳增强生命力的光线Necessary to continued existence or effectiveness; essential:极重要的，必不可少的：存在或有效性续所必需的；本质性的：例句：.Irrigation was vital to early civilization.(William H. McNeill).A vital component of any democracy is a free labor movement.(Bayard Rustin).灌溉对早期农业具有重要性.(威廉H.麦克乃尔).自由工人运动是任何民主所不可缺少的组成部分.(贝亚德·拉斯廷)Concerned with or recording data pertinent to lives:生命统计的：关于或记录生命主要数据的：例句：vital records.人口动态记录Biology Used or done on a living cell or tissue:【生物学】 活的， * 的：用于活细胞或组织的：例句：vital dyes; vital staining. * 染剂； * 染色Destructive to life; fatal:生死攸关的；致命的：例句：a vital injury.致命伤来源：Middle English 中古英语 from Old French 源自 古法语 from Latin vot3lis 源自 拉丁语 vot3lis from vota [life] * see g wei- 源自 vota [生命] *参见 g wei- 【引伸】vi.tallyadv.（副词）vi.talnessn.（名词）