句型14.
It is +形容词(possible, impossible, necessary等) +for+ sb.+ to do. 如：
It is impossible for me to finish this work before tomorrow.我明天之前完成此工作是不可能的。
句型15.
It is +(心理品质方面的)形容词+of + sb. +to do.= 主语+ be +形容词+to do.(常用的形容词有：kind, stupid; foolish, good, wise等。)如：
It is kind of you to help me.=You are kind to help me.你真好给我提供了帮助。
二、定语从句：
句型16.
由as引导的非限定性的定语从句。如：
As we have known, he is a most good student.众所周知，他是个很好的学生。请比较：It is well-known that he is a most good student.(前一个是定语从句，而后者是个主语从句。)
句型17.
由which引导的非限定性的定语从句。如：
He is a professor, which I have been looking forward to becoming. 他是个教授，那是我一直盼望的职业。(因为先行词professor是表示职业的名词，因此引导词用which，而不用who。
句型18.
由where, when引导的定语从句(其中包括限定性的或非限定性的。)如：
This is the house where I used to come.请比较：This is the house which / that I used to come to.
This is the day when I joined the Party.请比较：This is the day which / that I joined the Party on.
(说明：关于that与which之间的区别，请看关系代词that和which的区别。)
三、让步状语从句
句型19.
No matter what / which / who / where / when / whose+从句，+主句.(注意从句中的时态一般情况下用一般现在时态。)如：
No matter what you do, you must do it well.请比较：Whatever you do, you must do it well. 无论你做什么，一定要做好。
No matter where you go, please let me know.请比较：Wherever you go, please let me know.你无论去哪儿，请通知我。
(说明：这两种句型形式不同，而意义完全相同。)
(注意：I will tell whoever would like to read it. 句中的whoever不能用whomever来代替。因为它即作动词tell的宾语，又作后面从句的主语。) 四、条件状语从句
句型20.
本文来源：http://www.010zaixian.com/zuowen/yingyuxiezuosucai/172731.htm