The city is more beautiful than before.
The city is much more beautiful than
before.
意思都是,这座城市比原来漂亮多了.
beautiful是多音节,
所以比较级是more beautiful
much 可以修饰比较级.加深程度的意思.
你说前面只加much,应该是那种修饰不是多音节的形容词或副词的比较级,
比如规则变化中early-earlier,不规则变化good-better
例句：i get up much earlier than he does.
我起床比他早多了.
这里的much和上面一样,修饰比较级.加深程度的意思
much还可修饰不可数名词
i drink much wine and get dizzy
我喝多了酒,有点晕了
most 是形容词或副词的最高级,多音节单词变最高级时所需的
如上面的beautiful-more beautiful（比较级）-the most beautiful（最高级,注意the不能少）
例如；biejing is the most beautiful city in China.
北京是中国最美丽的城市
