Cooperative activity is essential to effective community work.
要把社區工作做好，協作活動是必不可少的。
It is essential that we present a united front.
至關重要的是我們要表現得團結一致。
Good posture is essential when working at the computer.
用電腦工作時良好的姿勢極其重要。
The agreement is essential to spurring economic growth around the world.
這項協議對于促進世界經濟的增長是至關重要的。
A degree is an essential prerequisite for employment at this level.
學位是做這級工作必備的先決條件。