1、as…as…结构：你和汤姆是一样好的孩子。
You’re a boy as good as Tom.=You’re as good a boy as Tom.
2、(1)too…to与 so…that sb. can’t…的句型转换：前者为简单句，主语只有一个，而后者为复合句，主语有两个，试比较：
The man was too angry to be able to speak.
The man was so angry that he wasn’t able to speak.
(2)too…to…与 not enough to句型的转换：
He is too young to get married.=He is not old enough to get married.
The book is too difficult for me to read.=
The book is not easy enough for me to read.
3、 形容词原级表示比较级含义：
约翰不象迈克那么苯。
John is not so stupid as Mike.
John is less stupid than Mike.
John is cleverer than Mike.
4、 用比较级表示最高级：约翰是班里最高的男生。
John is taller than any other boy in the class.
John is the tallest boy in the class.
