But those walls are increasingly porous.

然而，这些态度已经越来越。

Part of the problem, the country's porous borders.

问题的一部分在于这个国家的边界。

Dentin is pretty hard, but unlike enamel, it's porous.

牙本质非常硬，但与牙釉质不同，它是多孔的。

Have you noticed how porous or spongy good bread is?

你有没有注意过, 面包烤得好, 就能呈现非常明显的海绵状结构?

Bones might seem rock-solid, but they're actually quite porous inside.

骨头看上去和石块一样坚固，但它中心其实相当多孔。

To absorb sunlight, M.I.T. researchers created a porous disc of graphite flakes.

为吸收阳光，麻省理工学院的研究人员制造一个多孔渗水的石墨片盘。

They say a porous border is another reason people are coming in.

表示，边境漏洞百出是移民抵达的另一个原因。

Waves of stone, floating on sea foam all because the glass is porous.

漂浮在海面上的石头波浪，因为玻璃是多孔可渗透的。

Here's a look at how porous the border is between Kenya and Somalia.

接下来我为你带来肯尼亚和索马里两国的边界是多么驻守不严。

There, they mess with the fatty molecules a bit, ultimately making the barrier more porous.

在那里，它稍微搅乱脂肪分子，最终使屏障更容易渗透。

Then, at the end of 2017, the river had begun eating into the porous earthen wall itself.

在2017年底，河水又开始渗透混凝土。

They're saying that not rotating crops is not a good thing because the soil is less porous.

为，没有轮作农作物并不是件好事，因为土壤的透水性会减。

These vessels must not be porous, or they will let the liquids escape which we put into them.

但是这些器皿可不能“渗透”，不然盛上液体就会漏出去。

Winding passageways are narrow and dark. And the walls are made of unforgiving limestone, porous and with sharp edges.

蜿蜒曲折的通道狭窄又黑暗。石灰岩筑成的墙壁很难对付，气孔众多，而且边缘锋利。

These are porous molecular networks through which air can circulate. Their porosity gives them a huge surface area.

这些是多孔的分子网络，空气可以通过它循环。它的多孔性使它具有很大的表面积。

The reason for this is that, like many other porous materials, fresh snow is very good at absorbing sound.

原因是，像许多其的多孔材料，新鲜的雪很容易吸收声音。

Remember, do not sit on cushions, carpets, anything foam, or porous.

记住 不要坐在垫子 毯子 任何泡沫状 或有气孔的东西上面。

Their porous leaves purify the air by trapping carbon and other pollutants, making them essential in the fight against climate change.

它那多孔的叶子可通过捕获碳和其污染物来净化空气，从而使其在应对气候变化时起到至关重要的作用。

It is because the material of the blade is more compact or less porous in one case than in the other.

原因在于，优质刀片材料比劣质刀片材料更为密实，材质间隙更为细小。

There are other worries. Because its porous borders straddle ethnic groups, Liberia is always vulnerable to upheavals in neighbouring countries such as C? te d'Ivoire.

忧虑不仅于此。利比里亚边境族群分散、疏于防范，一直以来都受到来自邻国（如科特迪瓦）的侵扰。