1. 管理部門的同意就是所有雇用合同的必要條件。
   Agreement by the management is a sine qua non of all employment contract.
2. 愛瑪總可以這樣回首往事，她周圍的人全都門當戶對地婚配成親，這才是他們真正幸福的必要條件。
   She could always reflect that all parties concerned had married according to their stations, a prerequisite for their true happiness.
3. 格雷特已具備成為一名大演員的必要條件。
   Greta has got what it takes to become a great actress.

必要的英語翻譯：

條件的英語翻譯：