英语翻译求翻译和语法,（语法尽量详细） It is estimated that the average man or woman needs between seven-and-a-half and eight hours' sleep a night.
网友回答
估计平均每个男人和女人每晚都要睡7.5到8个小时.
It 形式主语
is estimated 谓语
that the average man or woman needs between seven-and-a-half and eight hours' sleep a night.
宾语从句,是真正的主语