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.
他生前的最後一段畫麪顯示他走過一列牽著警犬、圍成警戒線堵住人群的警察。
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.
在報道有可疑車輛後，一條200米長的警戎線切斷了倫敦一條主要的交通要道，造成更大的交通混亂。
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.
賴先生據說儅時沖破警察的警戒線，爬到陳先生所坐的地方，與其握手，然後把他推下去。

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.