cordon off

基本解释

The final footage of him alive shows him walking past the line of police dog handlers, who have formed a cordon blocking off Royal Exchange passage.
他生前的最后一段画面显示他走过一列牵着警犬、围成警戒线堵住人群的警察。
A 200m cordon was put in place, cutting off one of London's major transport arteries and causing further traffic chaos, after reports of the suspicious vehicle.
在报道有可疑车辆后，一条200米长的警戎线切断了伦敦一条主要的交通要道，造成更大的交通混乱。
blog.sina.com.cn
Mr Lai is said to have then broken through the police cordon, climbed to where Mr Chen sat, greeted him with a handshake - and then pushed him off the edge.
赖先生据说当时冲破警察的警戒线，爬到陈先生所坐的地方，与其握手，然后把他推下去。

During the EP-3 incident various pinheads furthered the impression of an American naval cordon off the Chinese coast.
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Some shopkeepers say they will cordon off parts of their premises to ensure they are small enough to be allowed to stay open.
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If police or soldiers cordon off an area, they prevent people from entering or leaving an area.