划分英语句子成分,it is necessary for us to learn English well.
问题描述：
划分英语句子成分,
it is necessary for us to learn English well.
答
赞三楼，很正确完整详细
答
it is necessary to learn English well.
it is 做形式主语 真正的主语是 to learn English well. 这样做的目的是避免句子头重脚轻 for us 是逻辑主语
答
现在这类型的句子可看成是一个句型It is +adj.+for sb.+to do sth其实it是形式主语,后面的to do sth才是真正的主语,for sb 其实是to do的逻辑主语.这样放置是为了避免头重脚轻,因为在英语中,只有一个句子呈现“孔雀...
答
it是形式主语，动词不定式to learn English well是真正的主语，is是谓语啰。