比较结构与情态推测 · PET 专项突破

这一节合并两个较小但高频的语法点。

一、比较结构（超出 KET 的部分）

基础复习：比较级 + than／the + 最高级 + in/of／as + 原级 + as

PET 新增的四种：

① not as/so ... as —— 不如

This film is not as good as the last one.
= The last one is better than this one.

② 比较级前的程度修饰

much better（好得多）／a lot cheaper／far more interesting
a bit / a little taller（高一点）／slightly more expensive

注意：不能用 very 修饰比较级。 very better（错）→ much better（对）

③ the + 比较级, the + 比较级 —— 越……越……

The more you practise, the better you become.
The older he gets, the happier he is.

这个句型在写作和口语里非常出彩，值得背下来。

④ 比较级 + and + 比较级 —— 越来越……

It's getting colder and colder.
The city is becoming more and more crowded.

⑤ one of the + 最高级 + 复数名词

He is one of the best players in the team.（注意名词要用复数）

二、情态动词表推测（PET 重点）

这是 KET 完全没有的用法：用情态动词表达「有多确定」。

对现在的推测：

确定度	情态动词	例
很确定是	must	He must be at home — his car is outside.
可能是	may / might / could	She might be in the library.
很确定不是	can't	He can't be 50 — he looks 30!

关键：肯定推测用 must，否定推测用 can't（不是 mustn't）。

mustn't 是「禁止」，不是「一定不是」
He can't be right.（他不可能对）✓
He mustn't be right.（意思变成「他不许对」）✗

对过去的推测：情态动词 + have + 过去分词

例	意思
He must have left.	他一定已经走了
She might have forgotten.	她可能忘了
They can't have finished so quickly.	他们不可能这么快做完
You should have told me.	你本该告诉我的（但没有）

should have done 表示「本该做而没做」，带责备或后悔的语气——写作和口语里很有用。

三、其他 B1 情态用法

用法	表达
请求（礼貌递增）	Can you → Could you → Would you mind + doing
建议	You should / ought to / had better（最好）
必要性	must（主观）／have to（客观）／needn't（不必）
过去的习惯	used to + 原形：I used to play football.
能力（各时态）	can / could / be able to（可配任何时态）

had better 的两个细节：后面接动词原形（had better go），否定是 had better not。

练习

用「越……越……」句型：你练得越多，进步越大。
填 must / can't：He ____ be hungry — he's just eaten a big meal.
改错：This book is very better than that one.
翻译：你本该早点告诉我的。
填空：He is one of the ____ (tall) ____ (boy) in his class.