The prison walls are very high.

监狱的围墙很高。

youdao

The next day in the yard, Tweener sits against one of the massive prison walls.

第二天，在院子里，Tweener坐在地上背靠一段宏伟的监狱围墙。

youdao

Outside the prison walls, rehabilitation and job programmes remain inadequate.

大牢之外，罪犯改造和职业培训工程仍然不足。

youdao

But the truth is that brutality continues, behind prison walls, occasionally glimpsed on the streets.

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And their neighbors beyond the prison walls will become new soft targets for the detainees' friends.

CENTERFORSECURITYPOLICY: Center For Security Policy

Hard experience with incarcerating such jihadists shows they are a threat to their jailers, fellow prisoners and populations beyond the prison walls.

CENTERFORSECURITYPOLICY: War courts for war criminals