一、much修饰不可数名词，many修饰可数名词。
两者都表示“许多”，但many修饰或代替可数名词（复数），与few（少数）相对；而much用来修饰或代替不可数名词（单数），与little（少量）相对。
二、much和many的用法
1、many修饰可数名词复数，如：There aremany people.
much修饰不可数名词复数，如：I have much money.
2、many作代词代表可数名词，如：Many of the students have great results.
much作代词代表不可数名词，如：Much of the air is fresh.
3、much还可以修饰动词，many不行。
如：I love you so much.
4、much还可以修饰比较级，many也不行。
如：He's much taller than her.
It's much more difficult than you thought.
扩展资料：
1、There are too many mistakes in this essay.
这篇文章错误太多。
2、He made ten mistakes in as many (= in ten) lines.
他在十行中就出了十个错。
3、New drivers have twice as many accidents as experienced drivers.
新驾驶员所出的事故是老驾驶员的两倍。
4、Don't take so many .
别拿这么多。
参考资料：much百度百科 many百度百科
