The boss made the workers work 12 hours in a day in the past(改为被动语态)

问题描述:

The boss made the workers work 12 hours in a day in the past(改为被动语态)
顺便翻译一下,并说出被动语态的什么结构

The workers were made to work 12 hours in a day in the past by the boss.
be made to do sth
翻译:过去,老板要工人们每天工作12小时.