重要，必要，主導，關鍵，根本，意義重大：

　　essential

　　e.g. Libraries are an essential part of this process, providing the only access for those who do not have the resources to purchase or access books and information on their own. 圖書館是在這個過程中一個必不可少地部分為那些靠自己無法獲得資源或者接觸書籍和信息的人，提供了唯一的途徑。

　　vital

　　e.g. It is vital to your mind, soul, body and your life on the whole that you stay in the present with all your thoughts and feelings. 總得來說,認識到自己所有的想法和感受都存在于現(xiàn)在,這對你的心理、靈魂、身體和你生命是非常重要的。

　　influential

　　e.g. In the US one of the most influential and lucrative professions is law, a field in which writing skills are indispensable.

　　在美國最有影響力收入也最高的職業(yè)之一就是律師，而這一行中寫作技能是絕對必要的。

　　overwhelming

　　e.g. He developed an overwhelming desire to exert power—to dominate, control and possess another person. 他發(fā)展出了壓倒性的權力欲望——去支配、控制和占有另一個人。

　　fundamental

　　e.g. This decision represents the fundamental interests of the people. 這個決定反映了廣大人民的根本利益。

　　indispensable

　　e.g. United Nations is an indispensable organization, but an organization that can only work because of the staff and their contribution and your dedication. 聯(lián)合國是一個必不可少的組織，但也是一個全因有了其全體職員的貢獻及他們的奉獻才能運作的組織。