1、essential

絕對必要的;必不可少的;基本的

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

將莊稼和放牧區分開絕對必要。

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

由于他們也必須進行短跑，因此速度至關重要。

基本的;本質的；根本的

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

大多數權威人士都同意，玩耍在孩子成長過程中起著非常重要的作用。

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

在這次審訊中，必須證明兩個基本因素：動機和時機。

（某學科的）基礎，基本知識

the essentials of everyday life, such as eating and exercise.

飲食、鍛煉等日常生活的要素

This has stripped the contest down to its essentials.

這就使比賽精簡到最基本的環節。

2、progress

進步；進展

The medical community continues to make progress in the fight against cancer.

醫學界在抗癌的斗爭中不斷取得進步。

The two sides made little if any progress towards agreement.

雙方在達成協議方面的進展甚微。

繼續進行；逐步發展

As the evening progressed, sadness turned to rage.

隨著夜幕逐漸降臨，悲傷變成了憤怒。

Life was hard, and it became harder as the war progressed.

那時候生活很艱難，并且隨著戰爭的持續愈發艱難了。