Many or Much
"Many" and "much" are actually quite similar in that they both mean "a large amount."
The way they are used grammatically is quite similar as well. However, despite their similarities, they're not interchangeable at all.
1. "Many" has less definitions than "much."
- a large number of.
"Many people agreed with her."
"How many years have you lived in Australia?"
- a majority of people.
This tends to be more formal and is used as a noun.
"It is important to consider the interests of the many."
- a large amount or a large degree.
"Kids nowadays just seem to have too much time on their hands."
"I didn't get much sleep."
To emphasise the difference when making comparisons, this can be used with comparative adjectives and adverbs.
"He looks much younger in person."
She’s walking much more slowly since her operation.
- nearly or approximately.
Usually this is used to say that something is similar to another.
"The twins are so much like their mother."
"The house is much like I remembered it."
- something of good quality.
We usually use this in the negative so it becomes a belittling or disapproving reference.
"I'm not much of a gardener."
"There's nothing much to watch on TV tonight."
- often or a large part of one's time.
"I haven't been there much."
"Have you seen Eve much recently?"
2. "Much" is usually used with adverbs in affirmative sentences.
You may have already noticed that affirmative sentences with "much" usually have adverbs like "so," "too," "as," or "very."
"I like her very much."
Not - "I like her much."
"I think you spend too much on shoes."
Not - "I think you spend much on shoes."
Using "much" by itself tends to be more formal.
"He spent much of his youth in America."
"There is much to discuss concerning the next campaign."
Or when you're making comparisons.
"The neighbouring cities are much the same."
"The visit was a much better experience than my previous one."
On the other hand, you can use "many" with or without adverbs.
"There are many dogs around today."
"They are so many dogs around today."
3. "Many" is used with countable nouns; "much" is used with uncountable nouns.
Many + plural countable nouns
"Many" is used with countable nouns that have both singular and plural forms. Countable nouns are usually things that are found as individual objects and easy to count.
"Many homes in Australia have at least one pet."
"There aren’t many female priests."
"How many cats do you have?"
Much + singular uncountable nouns
"Much" is used with uncountable nouns, usually in their singular form. These are nouns that are not easy to count, like abstract ideas, or liquor or gas, or certain foods.
"I feel bad for taking so much food."
"I haven’t got much change."
"How much information can you remember from the lecture?"
Money is an uncountable noun, but is often mistaken to be a countable noun.
"I don't have much money on me."
Not - "I don't have many money on me."
There are nouns that can be both countable and uncountable because they have several definitions.
For example, "time."
"I've read Lord of the Rings many times."
This refers to the number of occasions I've read Lord of the Rings.
"I don't have much time left to make dessert."
This refers to the amount of time I have left to make dessert.
Other nouns that can be countable and uncountable include "cheese," "wood," "vision" and "work."
4. There are more expressions and idioms with "much" than with "many."
Many - Most of these are kind of old fashioned.
in so many words
one too many
many happy returns
many moons ago
many a time
Much - Most of these are still quite common.
much too much
as much as you can do
a bit much
much less do something
not so much
so much for something