1、essential

绝对必要的;必不可少的;基本的

It was absolutely essential to separate crops from the areas that animals used as pasture.

将庄稼和放牧区分开绝对必要。

As they must also sprint over short distances, speed is essential.

由于他们也必须进行短跑，因此速度至关重要。

必需品;不可或缺之物

The flat contained the basic essentials for bachelor life.

那套公寓配有单身生活的基本必需品。

基本的;本质的；根本的

Most authorities agree that play is an essential part of a child's development.

大多数权威人士都同意，玩耍在孩子成长过程中起着非常重要的作用。

In this trial two essential elements must be proven: motive and opportunity.

在这次审讯中，必须证明两个基本因素：动机和时机。

2、priority

优先事项；最重要的事；当务之急

Being a parent is her first priority.

做好母亲是她的头等大事。

The government's priority is to build more power plants.

政府的首要任务是建造更多的发电站。

优先考虑；给…优先权

The school will give priority to science, maths and modern languages.

学校将重点发展理科、数学和现代语言。

The proposals deserve support as they give priority to the needs of children.

这些提议值得拥护，因为它们优先考虑了儿童的需求。

优先于；比…重要

The fight against inflation took priority over measures to combat the deepening recession.

抵制通货膨胀比抑制日益加剧的经济衰退更为重要。

I disagree with the premise that economic development has priority over the environment.

我不赞成经济发展应优先于环境保护这个前提。