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blockade; lockdown; sealing off (an area)
freezing (funds)
感染拡大を防ぐために都市が封鎖された。
The city was locked down to prevent the spread of infection.
道路が封鎖されて通行できなくなった。
The road was blocked and could not be passed.
経済封鎖が国民生活に深刻な影響を与えた。
The economic blockade had a serious impact on people lives.