lack
单词辨析：
指供小于求，即达不到需要或规定的数量。
There is no shortage of funds.
资金并不缺乏。
The bad harvest led to severe food shortages.
歉收造成食物严重短缺。
The war was lost because of a shortage of munitions.
战争因军火不足而失败。
指某物根本不存在或完全短缺，也指某人未在现场。
in the absence of evidence
缺乏证据
She noticed the absence of illustrations in the dictionary.
她发现那本词典里没有插图。
Please take care of my mother during my absence.
我不在时，拜托你照看我的母亲。
普通用词，指完全没有或不够充足，通常用于抽象事物。
Hard work can often make up for a lack of ability.
努力工作常可弥补能力的不足。
His lack of money kept him from going to the concert.
他因缺钱不能去听音乐会。
Lack of time prevented me from writing to my parents.
由于没有时间，我没能给父母写信。
指完全没有或短缺某物，强调所缺之物是必需的东西，使用范围比lack 要窄一些；也指因没有食物、钱等造成的贫困。
My son's always in want of money.
我儿子总是缺钱。
The kids are unhappy for want of love.
这些孩子因为缺乏爱而不幸福。
Many families are suffering from want.
许多家庭正遭受着贫困。
相关例句：
These people lack all understanding of scientific principles.
这些人对科学原理一窍不通。
There is no lack of precedents.
不乏先例。
The charges were dropped for lack of evidence
指控因证据不足而被撤销。
There is no lack of method in his way of thinking.
他的思维方法不乏条理性。
There is a lack of people wanting to start up new businesses.
有创业意愿的人非常匮乏。
Stress and lack of sleep can aggravate the situation
压力和睡眠不足会使情况恶化。