Construction material will be needed to build some types of disposal systems, for example, those with walls and roofs.

有些卫生设施，比如带有墙和房顶的，就需要建筑材料。

youdao

Available water. The amount of available water will determine whether disposal systems requiring water are a possibility.

可用水量决定了需要水的处理系统是否可行。

youdao

In countries without adequate sewage disposal systems, faeces and articles soiled with faeces may need to be disinfected before disposal.

在没有足够的污水处理系统的国家，可能需要在处置前对粪便和污有粪便的物品进行消毒。

youdao

It is spread through infected faeces and, once it enters the water supply, it is difficult to stop - especially in a country like Haiti which has almost no effective sewage disposal systems.

BBC: UN launches appeal to fight Haiti cholera epidemic

But as was pointed out in this recent blog, the brain actually has two different overarching pattern recognition systems at its disposal: the extrinsic and intrinsic.

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