1 比较级用来比较两个词条之间的关系，比较级是通过在形容词后加 er 或者在形容词之前加 more 构成。 它的反义句是通过在形容词前加 less 或者 not as构成。
Perfume sales were higher than cosmetics sales.
The accessories line is more exciting than the fragrance line.
2 Comparative adjectives with one syllable.
high - higher
low - lower
Cosmetics sales were lower than perfume sales.
形容词只有一个音节时，在其后加 er .在比较句中将than 置于形容与第二个词之间。
对于它的反义句 将 not as 置于形容词之前。在比较句中，在形容词与的哥词之间再加一个 as.
3 Comparative adjectives with three or more syllables.
Men's fragrances are less profitable than jewelry.
Jewelry is more successful than men's fragrances.
形容词有三个或者四个音节时，在其之前加 more ，反义词则在其之前加 less 或者 not as 构成比较句。
4 形容词有两个音节， 但结尾是 y 时， 将y 更改为i 加er， 形容词有两个音节，但结尾不是 y 时，在形容词前加 more. 对于它的反义句，在形容词前加 less 或者 not as.
Getting new customers is riskier than keeping old customers.
Women's perfume is more common than men's fragrances.
5 形容词不规则比较级形式
Adjective Comparative
good better
bad worse
much more
little less
far further
6 谈论某物的更多数量或数值时，在名词前加 more。 谈论可数事物的较少数值时，在名词前加 fewer。 谈论不可数事物的较少数值时，在名词前加 less。than 放在两个比较的名词中间。
The marketing department needs more money than the R&D department.
We produce fewer products than our competitor.
7 当比较的内容显而易见时，可以省略 than.
The company is more successful under new management.