It is necessary for us to master a foreign language.请问for us在句中做什么成分?

问题描述:

It is necessary for us to master a foreign language.请问for us在句中做什么成分?

动词不定式的逻辑主语要用for介绍,形成“for sb.to do sth",这种结构叫做不定式复合结构.句中It是形式主语,而把真正主语”for us to master a foreign language“放到整个句子后面,用以避免英语中最为忌讳的头重脚轻...