形容词、副词的比较级和最高级的用法：
当两种物体之间相互比较时，我们要用形容词或副词的比较级；
当相互比较的物体是三个或三个以上时，我们就要用形容词或副词的最高级。
形容词、副词的比较级和最高级的变化规律：
1. 单音节形容词或副词后面直接加-er或-est
tall—taller—tallest fast—faster—fastest
2. 以-e结尾的单音节形容词或副词直接加-r或-st
large—larger—largest nice—nicer—nicest
3. 以-y结尾的形容词或副词，改-y为-i再加-er或-est busy—busier—busiest early—earlier—earliest
4. 形容词或副词是重读闭音节时，双写最后的辅音字母，再加-er或-est hot—hotter—hottest big—bigger—biggest
5. 多音节形容词或副词前面直接加more或most
delicious—more delicious—most delicious
beautiful—more beautiful—most beautiful
6. 不规则变化
good (well)—better—best bad (badly)—worse—worst
常用的不规则变化的形容词的比较级和最高级:
bad worse worst
far farther (further) farthest（只指距离）(furthest)（用处较广）good better best
little less least
many／much more most
old elder ( older ) eldest（仅指人）(oldest)（指人和物）
形容词前如加 less 和 least 则表示较不和最不
important 重要 less important 较不重要 least important 最不重要
farther／farthest和further／furthest这些形式都可以指距离。further同样可以指“另外的／更多的”，主要和抽象名词一起用：
Further education will be meaningful．很快会得到更多的供应。
Further discussion would be pointless．继续讨论／辩论是无意义的。
I am too tired to go farther.
elder，eldest；older，oldest
elder和eldest主要表示的是长幼顺序而非年龄大小。主要用于表示家庭成员之间的长幼关系，如my elder brother（我的兄长／哥哥），her eldest boy／girl（她的长子／长女）。
但在than前不能用elder，只能用older：
He is older than I am．他比我年龄大。
A、形容词的原级可与as…as连用表示“和……同样……”，与not as／so…as
连用表不“不如……那样……”：
A boy of sixteen is often as tall as his father．一个16岁的男孩常长得和他父亲一样高。
He was as white as a sheet．他面色苍白如纸。．你煮的咖啡不如我母亲煮'sYour coffee is not as／so good as my mother的好。几个关于as...as的常见句型：
(1)as...as possible 尽可能
Please answer my question as soon as possible.请尽快回答我的问题。 (2)as...as usual/before 像往常一样像以前一样
She looks as pretty as before.她看起来和以前一样漂亮。
(3)长达as long as... (引导条件状语从句) 只要
It took us as long as three years to carry out the plan.我们花了长达三年的时间才完成这项计划。
(4)as far as 远至
He walked as far as the railway station yesterday evening.昨天傍晚，他一直散步到火车站。
(5)as well as
She cooks as well as her mother does.她烧菜烧得跟她母亲一样好。
一些带有as...as结构的常见短语归纳：
as busy as a bee像蜜蜂一样忙碌
as easy as ABC像ABC一样容易
as deep as a well像井一样深
as light as a feather像羽毛一样轻
as soft as butter像黄油一样软
as rich as a Jew像犹太人一样富裕
形容词比较级的用法: 形容词的比较级用于两个人或事物的比较,其结构形式如下:
主语+谓语(系动词)+ 形容词比较级+than+ 对比成分。也就是, 含有形容词比较级的主句
+than+从句。注意从句常常省去意义上和主句相同的部分, 而只剩下对比的成分。
Our teacher is than we are. 我们老师的个子比我们的高。
It is today than it was yesterday. 今天的天气比昨天暖和。
This picture is than that one. 这张照片比那张照片漂亮。
This meeting is than that one. 这次会议不如那次会议重要。
The sun is than the moon. 太阳比月亮大得多。
形容词最高级的用法: 形容词最高级用于两个以上的人和物进行比较, 其结构形式为:
主语+谓语(系动词)+the+形容词最高级+名词+表示范围的短语或从句。
She is student her class. 她是班上最好的学生。
Shanghai is one of cities China. 上海是中国最大城市之一
This is apple I have ever met. 这是我见到的最大的苹果。
Tom is boy in his basketball team. 汤姆是他们篮球队中个子最高的孩子。
