It is our duty to keep our classroom clean and tidy.这句话谁做主语谁做谓语
问题描述：
It is our duty to keep our classroom clean and tidy.这句话谁做主语谁做谓语
答
it是形式主语,真正的主语是后面的不定式短语to keep our classroom clean and tidy我问的是谁是主语谁是谓语谓语是is，真正的主语是后面的不定式短语to keep our classroom clean and tidy