1. Agreement by the management is a sine qua non of all employment contract.
   管理部門的同意就是所有雇用合同的必要條件。
2. Patience is a sine qua non for a good teacher.
   做個優(yōu)秀教師必不可少的條件是要有耐心。

qua

prep.（介詞）
In the capacity or character of; as:
以…的資格，或以…身份；作為：
例句：
The President qua head of the party mediated the dispute.
總統(tǒng)以黨的領(lǐng)袖身份出面調(diào)解這場爭端

來源：
Latin qu3 [feminine ablative sing. of] quo [who] * see k wo-
拉丁語 qu3 [] quo的陰性奪格單數(shù) [誰] *參見 k wo-