必需

Fluorine is one of the nonmetal which is indispensable to human body.

氟是一种原子量为19.00的卤族元素，也是人体必需的微量元素之一。

Fluorine is a necessary element for life of human and animals.

氟是人体和动物的必需元素之一，环境中的氟含量出现异常，往往会通过食物链的作用，引起人畜的氟中毒病症。

The fluorine is one of necessary nutritional trace element for human health.

氟是人体必需的微量元素之一，饮用水适宜的氟浓度为0.5～1mg／L。

Aiming to this, understanding the physical, chemical characteristic and the microstructure of fly ash is needed.

实现这一目标，了解粉煤灰的物理化学性质和结构特征是必需的。

And if you want curses, as the Monty Python Flying Circus skit reminds us, you'll need to go down the hall.

如果你想骂人，就像巨蟒飞行马戏团的幽默故事提醒我们的那样，你必需进入大厅。

It is widely used in medical industry, food industry and fodder industry, and its usage is enlarging.

赖氨酸是人、畜自身不能合成的必需氨基酸之一，被广泛应用于医药工业、食品工业和饲料加工业，而且应用领域仍在不断拓宽，具有很好的市场前景。

They speak sterling Arabian language, have a broad web of social relations, know very well the folkway and the situation of those countries and especially keep some kind of contact with the companies that you are going to do business with.

这些代理商操着纯正的阿拉伯语，有着广泛的社会关系网，熟悉民风国情，特别是同你所要与之洽谈的企业有着直接或间接的联系。这些都是你做生意所必需的。

FOXP3(the forkhead/winged-helix transcriptional regulators P3) is expressed specifically in regulatory T cells, and exerts great influence on the development and function of Treg cells.

国外多个研究小组已证明FOXP3(称叉头状/翼状螺旋转录因子)在Treg细胞上特异性表达，且对Treg细胞的发育和功能是必需的。

They are necessary for the formal education of all children.

他们所必需的正规教育的所有儿童。

In the next phase of the System F6 program, Orbital will be responsible for the detailed design and ground testing of the new technologies, architectures and programmatic concepts required to successfully fractionate a space system.

合同规定，在F6系统计划进行的下一阶段，将由轨道科学公司负责新技术，新结构及程序化概念的详细设计和地面测试，这些都是成功分析太空系统所必需的。

I am accused of being overreligious," she said in her quiet, frank manner,"but that does not prevent me thinking the children very cruel who obstinately commit such suicide.""

客人们在卡罗利娜·埃凯家里，举止就文雅一些，因为卡罗利娜的母亲治家很严厉。

Designed by French fashion house Herm è s, this elegant uniform was manufactured in our home, Hong Kong, and was the first without a hat.

由著名品牌 Herm è s 设计，这件高贵的制服是香港本土制造，是我们第一套不配帽子的制服。