警察拦住了抗议者。

The police ___held the protesters ___back.

设置了路障以阻挡人群。

Barricades were erected to ___hold the crowd ___back.

紧急服务人员将围观者挡在燃烧的建筑之外。

Emergency services ___held the onlookers ___back from the burning building.