(1)It’s+adj.+for (of)sb. to do sth.
当不定式作主语时,通常用it作为形式主语,而把真正的主语不定式结构后置。例如:
To meet you is a great pleasure. =It is a great pleasure to meet you.非常高兴见到你。
To plant trees every year is necessary.= It is necessary to plant trees every year.每年植树是必要的。
这种结构往往还要有一个逻辑主语。一般使用下面的结构:
1)It is +adj. +of sb.+to do sth.
It is selfish of you to eat the whole birthday cake.你真是太自私了,吃光了整个蛋糕。
2)It is +adj. + for sb. + to do sth.
It is difficult for me to learn English well.对我来说学好英语太难了。