北师大版英语八年级上册Unit3 原级、比较级、最高级的构成和用法

原级、比较级、最高级的构成和用法

回顾：原级的构成和用法

l)构成：形容词，副词的原级形式是形容词

2)用法：表示双方在程度，性质，特征等某方面相等时，用" as 十原级形容词或副词十as"的结构；

表示双方不相等时，用" not so (as)十原级形容词或副词十as"的结构；

表示一方是另一方的若干倍时，用"倍数十as十原级形容词或副词十as"的结构．

e.g. Ms．Sun speaks English as fluently as you．

This building looks not so (as) high as that one．

This room is three times as large as that one.

1.比较级和最高级的构成

1）加-er, -est构成比较级和最高级。

单音节形容词和副词以不发音的-e结尾的

high higher highest safe safer safest hard harder hardest late later latest small----smaller----smallest large----larger----largest

new----newer----newest nice----nicer----nicest

辅音字母要双写的情况以辅音加-y结尾的情况

Big bigger biggest dry drier driest Hot hotter hottest merry merrier merriest Thin thinner thinnest easy easier easiest

2) 加more, most构成比较级和最高级

多音节的形容词由形容词加-ly构成的副词

expensive more expensive most expensive

slowly more slowly most slowly

carefully more carefully most carefully

highly more highly most highly

以-ful, -less, -able, -ous, -ive, -ing等结尾的双元音形容词

useless more useless most useless

serious more serious most serious

分词形容词tired,pleased及glad,often,real, right,wrong等单音节形容词。Tired more tired most tired

Glad more glad most glad

3）下列形容词、副词的比较级和最高级可有两种构成方法．

cruel crueler cruelest more cruel most cruel

often oftener oftenest more often most often

strict stricter strictest more strict most strict

friendly friendlier friendliest more friendly most friendly

4)形容词。副词的比较级和最高级的不规则构成法

Good/well better best

Bad/ill/badly worse worst

Many/much more most

Little less least

Far farther/further farthest/furthest

Old older/elder oldest/eldest

2 比较级的表示法：主语+be+比较级+than…

主语+谓语+比较级+than…

1)不同主语的比较，

①双方比较，表示一方超过另一方时，用"比较级十than"的结构表示

He is two years younger than I.

②表示一方不及另一方时，用" less十原级十than"的结构表示

This room is less beautiful than that one

2) 同一主语不同方面的比较

She is now happier than she has ever been

用于修饰比较级的词：even, （very）much, far, a lot, still, yet. a bit，a little，still，much，yet，by far

注意：by far通常用于强调最高级．用于比较级时，一般放在比较级的后面，如在前面，应在二者中间加" the"．如

He is taller by far than his brother.

He is by far the taller of the two brothers.

表示一方超过另一方的程度或数量，可在比较级前加上上述表示程度的副词，以加强语气。

He works even harder than before.

4）某些以一or结尾的形容词进行比较时，用to代替than．(这些词有inferior [in'fiəriə]低人一等的| 下等的| 下级的，superior [sju:'piriə]上级的；优秀的，

出众的；高傲的，junior（下级的，年少的），senior（年长的，高级的），prior（较早的，在先的）等．Junior school小学，senior school中学例如：He is superior to Mr Wang in mathematics

5）在比较从句中为了避免重复，我们通常用that(those)，one(ones)代替前面出现的名词。that指物，one既可指人，也可指物．that可代替可数名词单数和不可数名词，而one只能代替可数名词.例如：

The book on the table is more interesting than that on the desk.

A box made of iron is stronger than one made of wood．

二，as, little, few, elder等在比较级中的用法。

as 用于比较级

1）As +形容词或副词原级+as

Tom is as tall as Mike.

2) as +形容词原形+A+名词+as

He is as good a student as you.

3) 倍数+as+形容词或副词原级+as

This room is three times as large as that one.

提到倍数用法，

补充：表示倍数的比较级有如下几种句型：

1) A is three(four，etc) times as big(high，long，wide，etc．) as B．例如：

Asia is four times as lareg as Europe，亚洲是欧洲的四倍大．(亚洲比欧洲大

三倍．)

2) A is three(four，ete) times the size(height，length，width，ete) of B．例如；