It was impossible for lost time to be made up这句话的结构请问这句话是什么结构主语是什么，是不定式还是lost time？我看的材料说是不定式做主语成分
问题描述：
It was impossible for lost time to be made up这句话的结构
请问这句话是什么结构
主语是什么，是不定式还是lost time？我看的材料说是不定式做主语成分
答
it 做形式主语，真正的主语确实是不定式to be made up.
To be made up was impossible for lost time.
答
不定式的复合结构
It is/was +形容词+for sb/sth to do sth
记住这个句型，是很常用的不错句型哟~！
it是形式主语，真正主语：for sb/sth to do sth
for lost time to be made up 挽回已逝去光阴
It was impossible for lost time to be made up 挽回已逝去光阴是不可能的。
答
it 做形式主语,to be made up是不定式做后置定语修饰 lost time.
原句可以理解为 making up the lost time was impossible
lost time to be made up整个做主语,强调弥补这个动作
答
整体结构是主系表，成分如下：
It was impossible for lost time to be made up.
形式主语 系动词 表语 真正主语