They experimented with mineral additives to reduce the temperatures needed to prepare the materials .

他们试验加入矿物添加剂来降低水泥原料所必需的加热温度。

Are these efforts still needed ?

这些尝试还有必要吗？

They have not needed to .

他们没有必要这么做。

The rate cut was needed .

降低利率是必要的。

Other innovations will also be needed .

其他的创新也是必要的。

It also provides needed annotation .

书中还有一些必要的注解。

Will we make the needed changes ?

我们会做出必要的改变吗？

To pass the needed reforms , he may need to appeal to the opposition .

为通过必需的改革法案，卢拉可能需要向反对党求助。

Sometimes medication is needed as well .

有时用些药物辅助治疗也是必要的。

B12 and folic acid together are needed for making normal cells , including blood cells .

维生素b12和叶酸都是合成细胞所必需的，其中也包括血细胞。