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- Air consists chiefly of nitrogen. 空气主要由氮气组成。
- Maintenance of PC is in my element. 我对电脑的维修保养很在行。
- He had to work hard for the maintenance of his family. 他为了养家不得不去拼命工作。
- The main reservoir of nitrogen is the atmosphere. 氮的主要蓄存库是大气层。
- What is the percentage of nitrogen in air? 空气中所含的氮的比例是多少?
- The crux of the matter was a lack of nitrogen. 问题的关键在于缺少氮。
- The major problem is the maintenance of the child. 主要的问题是孩子的抚养费。
- Repair and maintenance of machinery and equipment. 机械及设备的维修和保养;
- Maintenance of business car for QM dept. 质量部门车辆维修保养;
- Maintenance of order is no easy job at this time. 这时候要维持秩序可不是件容易的事。
- Among the blue-green algae are many species of nitrogen fixation. 许多种蓝藻有固氮的能力。
- He spent a lot on the maintenance of his car. 他在汽车维护上花了不少钱。
- Urea is commonly used as the source of nitrogen in foliage sprays. 尿素作为氮素给源普遍地应用于叶面喷布。
- In charge of maintenance of equipment. 测试系统设备维护。
- Is the maintenance of the premises adequate? 工厂厂房维护是否充分?
- Necessary for the maintenance of life processes. 维持生命过程所必需的
- Has an atmosphere, which is mainly made up of nitrogen. 它拥有主要由氮组成的大气。
- One who is responsible for the maintenance of a golf course. 高尔夫球场看管员负责看护高尔夫球场的人
- The amount of nitrogen needed will increase as yield increases. 随着产量增加，需氮量也要增加。
- She worked hard to earn money for the maintenance of her family. 她卖力干活为了挣钱养家糊口。
