Cooperative activity is essential to effective community work.

　　要把社區工作做好，協(xié)作活動(dòng)是必不可少的。

　　It is essential that we present a united front.

　　至關(guān)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(shí)良好的姿勢極其重要。

　　The agreement is essential to spurring economic growth around the world.

　　這項協(xié)議對于促進(jìn)世界經(jīng)濟的增長(cháng)是至關(guān)重要的。

　　A degree is an essential prerequisite for employment at this level.

　　學(xué)位是做這級工作必備的先決條件。