必需的

Therefore the governance of pollution has become widely problem which attracting people's attention. In Agriculture, Cupper and zinc are required microelements of plant.

在农业生产过程中，铜和锌既是植物生长发育所必需的微量元素，同时过量的铜和锌也将对作物产生严重的危害，并由此引发一系列食品安全问题。

Cytosine methylation is required for mammalian development and is often perturbed in human cancer.

胞嘧啶甲基化对哺乳动物的正常发育是必需的，而且常常在人类的癌症中发生异常。

India is the only Bric country without such a fund, de rigueur among up and coming emerging economies.

印度是金砖四国中唯一没有此类基金的国家，而对一个积极进取的新兴经济体来说，这样一个基金似乎是必需的。

Contrast is necessary for the human eye to be able to discriminate between objects and their background.

差别对人类的眼睛是必需的可以在物体和他们的背景之间区别。

As the one of three primary colors to realize full-color electroluminescence display, it has practical significance to improve properties of blue electroluminescence device.

作为实现全彩色电致发光显示必需的三基色之一，蓝色电致发光器件性能的改善和提高具有重要的现实意义。

Such excitatory neurotransmitters are necessary for normal alertness, memory, muscle tone and co-ordination, emotional responses, endocrine gland secretions, heart rate and blood pressure control and a host of other functions, all of which may be impaired by benzodiazepines.

这些兴奋神经传导质对正常的警觉，记忆，肌肉的紧张性和和谐性，情感反应，内分泌，心率和血压控制以及许多其他功能是必需的，所有这些都会被苯二氮卓类药物损坏。

A keen awareness of right from wrong is essen tial for determining appropriate social behavior .

对正误的深刻认识是判定得体的社会行为所必需的。

A complete spectrum of essential minerals ,in balanced ,highly bioavailable forms !!!

一个完整的生活必需的矿物质，在均衡的，高度生物利用形式！

These results have profoundly changed astronomers' views of BHs: More than just exotica needed to explain rare AGNs, BHs are becoming an integral part of our understanding of galaxy formation.

这些结果深深地改变了天文学家对黑洞的认识：比解释活动星系核更吸引人的是，黑洞正成为解释星系形成必需的一部分。

In particular, reinterpretation of the growth rate in terms of some form of expected value is required.

特别是，重新解释的成长在一些形式上的预期值率是必需的。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。