We say narrow crannies, and we can give no more just idea of those dark, contracted, many-angled alleys, lined with eight-story buildings.

我们说窄缝，是因为我们对那些阴暗、狭窄、转弯抹角、两旁夹着倾斜破旧的九层楼房的小巷找不出更确切的表达方式。

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Moving in groups of eight, police made their way through the alleys of Jacarezinho, searching houses, while armoured cars took up position beside rubbish dumps, news agency AFP reported.

BBC: Brazil drugs raids: Police surge into north Rio slums