Definition: a type of fence that stops people from going into an area Level: B2
一个临时路障被放置在建筑工地周围以确保安全。
A temporary ___barrier was placed around the construction site to ensure safety.
只有授权人员才能用他们的钥匙打开这道闸门。
Only authorised personnel can open the ___barrier with their keys.
高高的屏障阻止了任何人非法穿越边境。
The high ___barrier prevented anyone from crossing the border illegally.
