1.
Fresh air gives you the oxygen you need. all the ceils of the body must have oxygen. They use it to change food into energy.
新鲜空气为人们提供所需要的氧气。身体全部细胞都需要氧气。细胞利用氧把食物变成能。
2.
For the same amount of carbon, there is twice as much oxygen as in carbon monoxide.
同一份量的碳，所需要的氧的分量却是一氧化碳的二倍。
3.
As is known to us all, the burning of any fuel requires oxygen.
众所周知，任何燃料的燃烧都需要氧气。
4.
The oxygen content in the vent pipe of the equipment has to be checked for the concentration of O2 to get the required amount of Nitrogen.
需要检查设备放空管线中氧气的浓度，来确定所需要的氮气的量。
5.
It is mainly applied to increasing oxygen content in fishpond, so as to provide sufficient oxygen required by fish growing.
主要用于增加鱼池水中含氧量，满足鱼类生长发育所需的氧气。
6.
Oxygen is necessary for life.
氧气是生命所必需的。
7.
exercise that increases the need for oxygen.
增加氧气需要量的练习。
8.
life sustained in the presence of air or oxygen.
需要空气或氧气的生活。
9.
A stable radical intermediate is a necessary requisite to loss of carbon dioxide.
一个稳定自由基的中间体是脱除二氧化碳所需的必要条件。
10.
Blood must circulate properly in the head to supply the fresh oxygen the brain cells need.
血液必须在大脑中适当循环，为脑细胞提供所需要的新鲜氧气。
11.
We need $50 to make up the sum required.
我们需要五十元以补足所需要的数目。
12.
Raw material is what we are in need of.
原材料是我们所需要的。
13.
An electric fan will be just the ticket for me
电扇正是我所需要的
14.
Ray!You are the very person I want!
雷，你正是我所需要的人！
15.
I want all the juicy details.
我需要所有有趣的细节。
16.
all the flowers want watering.
所有的花都需要浇水。
17.
Find the particular item you are looking for.
找到你所需要的条目，
18.
The kind of Chinese elite we need
我们所需要的华文精英