1、原级比较的时候我们在肯定句可以用as +原级+as, 而在否定句中我们可以用not as/so+原级+as，如you should study as hard as Tom
2、A is to B what/as C is to D表示A和B的关系和C与D的关系具有可比性，如reading is to the mind as excise to the body,读书对于思想好比运动对于身体一样
3、常用的比较结构有比较级+than，和not+比较级+less than, 如the book is not more interesting than that one这本书不能那本书有趣
4、以ior结尾的含有比较意义的形容后用to而不是than，如superior, inferior, senior, junior,major, anterior, prior, posterior等，如he is three years junior to me
5、比较级+and+比较级或者more and more+形容词表示越来越，如when writer comes, the weather is colder and colder
6、the+比较级...the+比较级...结构，表示越来越，说明情况随着前面条件的变化而变化，如the more careful you are, the fewer mistakes you will make
