Much and Many

We find a lot of mistakes with the use of much and many. Actually, the mistakes are mostly with much.

With countable nouns (可算名詞), we use many, regardless of whether the sentence is grammatically positive or negative, or a question:

• (+) She's got many friends.
• (-) She has not taken TOEFL many times.
• (Q) Will you apply to many schools this year?

You can substitute a lot of in any of the above sentences.

But with uncountable nouns (不可算名詞), we use a lot of in grammatically positive sentences:

• (+) I have a lot of time this week.
• (+) He made a lot of money last year.

However, we can use much or a lot of in grammatically negative sentences and questions:

• (-) I don't have much time this week.
• (-) I don't have a lot of time this week.
• (Q) Did he make much money last year?
• (Q) Did he make a lot of money last year?

Here's the British Council's page on this.

Please use English well!