block off
US /blɑːk ɑːf/
UK /blɑːk ɑːf/

1.
封锁, 堵塞
to close a road, path, or entrance so that people cannot use it
:
•
Police had to block off the street due to the accident.
由于事故,警方不得不封锁街道。
•
They decided to block off the old entrance to prevent unauthorized access.
他们决定封锁旧入口,以防止未经授权的进入。