所有单音节词，双音节词 例如：easy（双音节），hot，cold等！
三音节及以上的词的比较及就要使用more了！例如：beautiful
三音节及以上的词的比较级才加more，其他的都是er ，ier，或特殊变化。
简单点，就是多音节通常在单词前加MORE(比较级)MOST（最高级）
而其他的都是直接有的
例：一般加er
以e结尾er
以辅音字母加Y结尾把Y改为i加er
闭音节形容词末尾只有一个辅音字母，双写辅音字母后加er
另外有几个不规则变化的
最高级就是上面所说的一样，只是把er变成est就OK了
大多数形容词（性质形容词）和副词有比较级和最高级的变化，即原级、比较级和最高级，用来表示事物的等级差别。
原级即形容词的原形，比较级和最高级有规则变化和不规则变化两种。
1) 规则变化
单音节词和少数双音节词，加词尾-er，-est来构成比较级和最高级。
构成法 原级 比较级 最高级
一般单音节词 tall(高的) taller tallest
末尾加-er,-est great(巨大的) greater greatest
以不发音的e结尾和以- le结尾的双音节词只加-r,-st
nice(好的) nicer nicest ，able（有能力的) abler ablest
以一个辅音字母结尾的闭音节单音节词，双写结尾的辅音字母，再加-er，-est
big(大的) bigger biggest
hot热的) hotter hottest
"以辅音字母+y"结尾的双音节词改y为i，再加
-er，-est easy(容易的)
easier easiest ，busy(忙的) busier busiest
少数以-er，-ow结尾的双音节词末尾加-er，-est
clever(聪明的) cleverer cleverest
narrow(窄的) narrower narrowest
其他双音节词和 important(重要的)
多音节词，在前 more important
面加more，most most important
来构成比较级和 easily(容易地)
最高级。 more easily
most easily
2) 不规则变化
原级 比较级 最高级
good(好的)/ better best
well(健康的)
bad (坏的)/ worse worst
ill(有病的)
old (老的) older/elder oldest/eldest
much/many(多的) more most
little(少的) less least
far (远的) farther/further farthest/furthest
比较级形容词或副词 + than
You are taller than I am./ You are taller than me.
The lights in your room are as bright as those in mine.
注意：
1）要避免重复使用比较级。
(错) He is more cleverer than his brother.
(对) He is more clever than his brother.
(对) He is cleverer than his brother.
2）要避免将主语含在比较对象中。
(错) China is larger that any country in Asia.
(对) China is larger than any other country in Asia.
3）要注意对应句型，遵循前后一致的原则。
The population of Shanghai is larger than that of Beijing.
It is easier to make a plan than to carry it out.
4）要注意冠词的使用，后有名词的时候，前面才有可能有名词。
比较：Which is larger, Canada or Australia?
Which is the larger country, Canada or Australia?
She is taller than her two sisters.
She is the taller of the two sisters.
可修饰比较级的词
1）a bit, a little, rather, much, far, by far, many, a lot, lots, a great deal, any, still, even等
2）还可以用表示倍数的词或度量名词作修饰语。
3）以上词(除by far)外，必须置于比较级形容词或副词的前面。
典型例题:
1） ---- Are you feeling ____?
---- Yes，I'm fine now.
A. any well B. any better C. quite good
D. quite better
答案：B. any 可修饰比较级，quite修饰原级，well的比较级为better.
2）The experiment was____ easier than we had expected.
A. more B. much more C. much
D. more much
答案：C. much可修饰比较级，因此B，C都说得通，但easier本身已是比较级，不需more，因此C为正确答案。
3）If there were no examinations, we should have ___ at school.
A. the happiest time B. a more happier time
C. much happiest time D. a much happier time
答案：D。
比较级和最高级一般都要一起讲吧
the + 最高级 + 比较范围
1) The Sahara is the biggest desert in the world.
形容词最高级前通常必须用定冠词 the，副词最高级前可不用。
形容词most前面没有the，不表示最高级的含义，只表示"非常"。
It is a most important problem.
=It is a very important problem.
注意： 使用最高级要注意将主语包括在比较范围内。
(错) Tom is the tallest of his three brothers.
(对) Tom is the tallest of the three brothers.
2) 下列词可修饰最高级，by far, far, much, mostly, almost
This hat is nearly / almost the biggest.
注意：
a. very可修饰最高级，但位置与much不同。
This is the very best.
This is much the best.
b. 序数词通常只修饰最高级。
Africa is the second largest continent.
3) 句型转换：
Mike is the most intelligent in his class.
Mike is more intelligent than any other student in his class.
4) "否定词语+比较级"，"否定词语+ so… as"结构表示最高级含义。
Nothing is so easy as this.
=Nothing is easier than this.
=This is the easiest thing.
英语形容词的比较级、最高级用法解析：）~~
一：单音节或部分双音节的词的比较级最高级的变法:
1.一般情况下直接加er或est.
如:short→shorter→shortest
2.以字母e结尾的形容词和副词加r或st
如:nice→nicer→nicest
3.以辅音字母y结尾的Y改为I加er,est
如:happy→happier→happiest
4.重读闭音节结尾的双写结尾辅音字母加er或est
如:fat→fatter→fattest
5.特殊形式
good/well→better→best
many/much→more→most
ill/bad(badly)→worse→worst
little→less→least
old(eld)→older→oldest(elder/eldest)
far→farther→farthest(further/furthest)
多音节的形容词和副词的比较级.最高级.:比较级在形容词.副词前面加more,最高级在形容词.副词前面加most.
如:beautiful→more beautiful→most beautiful
(而且在句子中,形容词最高级前必须加the.)
二：形容词加ly变成的副词的比较级和最高级用more或most.
如:showly,happily
由动词的过去分词形式的形容词:用more或most表示比较级和最高级.
如:tired→more tired→most tired
语法-轻松英语-洪恩在线,这里面有分类的详细介绍，可以看看：）~~
http://www./eng/pub/yufac/
英语语法专区，各个语法点：）~
http://www./album/resource/20051010_grammar/#
little-less-least,
many\much-more-most,
well\good-better- best
bad-worse-worst,
far-rarther\further-farthest\furthest,
difficult-more difficult-the most difficult,
