In a built-up area, signals bounce off buildings, trees, and at some frequencies even people.

在建筑物密集的地区，信号会被建筑物、树木反弹，某些频率甚至能被人反弹。

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Concept: in a highly built-up area, closed in on all sides, this house offers both privacy and light.

概念：在一个高密度区域，周边房子都靠得很近，但这所房子既提供了私密性，又提供了光亮的环境。

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But going beyond the ring-road to the suburbs, the total built-up area has a population of 10m.

但是在环城公路以外的城郊，整个结合区有人口1000万。

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In the past six years its built-up area has expanded by more than 60%.

ECONOMIST: Inner Mongolia

Cleveland actually lost people, with a population decline of 8%, while expanding its built-up area by 33%.

ECONOMIST: They can yet be resurrected | The

Wildlife experts have said the sighting of the normally-shy deer so close to a built-up area is "extremely rare".

BBC: 'Shy' deer with sheep near homes in Lancashire