requisite
英 ['rekwɪzɪt]
美['rɛkwəzɪt]
	    - adj. 必备的,必不可少的;需要的
 - n. 必需品
 
英英释意
- 1. anything indispensable;
 - "food and shelter are necessities of life"
 - "the essentials of the good life"
 - "allow farmers to buy their requirements under favorable conditions"
 - "a place where the requisites of water fuel and fodder can be obtained"