一. 形容词及副词；
1. 形容词：用来修饰限定名词的单词，翻译成“……的”，通常放在名词之前。
e.g. blue sky (blue蓝色的，用来修饰sky)
hardworking students (hardworking努力工作的，用来修饰students)
2. 副词：通常用来修饰动词的单词，翻译成“……地”，通常放在动词之后；除此之外，副词也可以修饰形容词，副词以及它们的比较级。
e.g. run fast (fast快地，用来修饰run)
speak quickly(quickly快地，用来修饰speak)
quite beautiful (quite 相当，非常，用来修饰形容词beautiful)
quite well (quite相当，非常，用来修饰副词well)
3. 形容词通常加-ly转换为副词，但以-ly结尾的单词不一定是副词(friendly有好多，lovely可爱的，lonely孤单的，deadly致命的等)。
e.g. beautiful——beautifully
usual——usually
二．原级，比较级及最高级；
1. 原级
⑴定义：两者进行比较，后者与前者在某方面相同或不同。
⑵形式：
①肯定形式：…as +形容词或副词的原级+ as…，表示前者和后者一样；
②否定形式：…not as/so +形容词或副词的原级+ as…，表示前者不如后者。
e.g. He is as friendly as his sister.
He is not as/so friendly as his sister.
She works as hard as Mary.
She doesn’t work as hard as Mary.
2. 比较级
⑴定义：两者进行比较，前者比后者在某方面更怎么样。
e.g. Tom is taller than me.
Mary is less outgoing than Jane.
⑵形容词或副词比较级的变化规则:
①规则变化：
一般在词尾加-er；
e.g. high----higher
tall----taller
short----shorter
以字母e结尾的词在词尾加-r；
e.g. fine----finer
late----later
以重读闭音节结尾的末尾只有一个辅音字母时，先双写该辅音字母在加-er；
e.g. big----bigger
thin----thinner
fat----fatter
以辅音字母加y结尾的双音节词，先把y改为i再加-er；
e.g. easy----easier
funny----funnier
early----earlier
多音节词和部分双音节词，在词前加more或less；
e.g. beautiful----more/less beautiful
interesting----more/less interesting
comfortable----more/less comfortable
②不规则变化（特殊记忆）：
e.g. good/well----better
bad/badly----worse
many/much—more
little----less
far----farther/further
⑶形式：…形容词或副词的比较级+ than…
e.g.The book is more interesting than that one.
He runs faster than me.
Tom is smarter than Tina.
⑷比较级中的肯定句变为否定句，疑问句以及疑问句的肯定回答和否定回答。
e.g.①肯定句：Tom is smarter than Tina.
否定句：Tom is not smarter than Tina.
疑问句：Is Tom smarter than Tina?
肯定回答：Yes, he is. (Tom is smarter than Tina.)
否定回答：No, he isn’t.(Tina is smarter than Tom.)
②肯定句：She works harder than Mary.
否定句：She doesn’t work harder than Mary.
疑问句：Does she work harder than Mary.
肯定回答：Yes, she does.
否定回答：No, she doesn’t.
⑸用法：
①句中出现than要用比较级；
e.g. She is more outgoing than Mary.
It was one fourth cheaper than the market price.
②通常情况下，形容词或副词的比较级前不加the，但若对两者进行比较，句中又无than出现，则常用“the +比较级+ of+比较范围（只有两者）”的结构;
e.g. He is the smarter of the two boys.
She is the taller and the more beautiful of the two sisters.
③“the +比较级…the +比较级”意为“越来越……”,表示一方随另一方的改变而改变；
e.g. The sooner,the better.
The harder you study, the better grades you will get.
④“比较级and 比较级”，意为“越来越怎么样”;
e.g. more and more
better and better
more and more outgoing
3. 最高级
(1)定义：三者或三者以上进行比较，其中一者在某方面超过其他几者，后面可用of（in），短语等来说明比较的范围。常与冠词the连用（形容词最高级前面要加冠词the，副词最高级前的the可以省略）。
(2)形式：…+形容词或比较级的最高级+…
(3)形容词或副词最高级的变化规则
①规则变化：
一般在词尾加-est；
e.g. high----highest
tall----tallest
short----shortest
以字母e结尾的词在词尾加-st；
e.g. fine----finest
late----latest
以重读闭音节结尾的末尾只有一个辅音字母时，先双写该辅音字母在加-est；
e.g. big----biggest
thin----thinnest
fat----fattest
以辅音字母加y结尾的双音节词，先把y改为i再加-est；
e.g. easy----easiest
funny----funniest
early----earliest
多音节词和部分双音节词，在词前加most或者least；
e.g. beautiful----most/least beautiful
interesting----most/least interesting
comfortable----most/least comfortable
②不规则变化（特殊记忆）：
good/well----best
bad/badly----worst
many/much----most
little----least
far----farthest/furthest
old----oldest/eldest
(4)用法：
①最高级用于三者或三者以上之间的比较。使用最高级通常用in, among, of引导的介词短语说明范围；
e.g. Tom is the most outgoing student in our class.
You do your homework the most carefully among all of us.
②the +最高级+ of +比较范围，意为“……之中最……”;
e.g. He is the tallest of the three students.
③one of the +最高级，意为“最……中之一”。
e.g. Yaoming is one of the tallest players in the world.
Mary is one of the best students in our class.
(5) “the most +形容词或副词原级”结构与“a most +形容词或副词原级”结构的比较;
“the most +形容词或副词原级”结构中的most表示“最……”,用于最高级；而“a most +形容词或副词原级”结构中的most表示“非常”。
e.g. It’s the most touching story .
It’s a most touching story.