We generally use “many” in questions and negative sentences with countable noun.
Example:
- Have you got many pens in your bag?
- She doesn’t have many cars.
2). MUCH
We also use “much” in questions and negative sentences but with uncountable noun.
Example:
- Is there much water left?
- We don’t spend much money.
3). A LOT OF/ LOTS OF
We mostly use “a lot of/lots of” in positive sentences with both countable and uncountable noun.
Example:
- He drinks a lot of beer in the pub.
- I can speak lots of languages.
NOTE 1: We often use plenty of instead of a lot of. However, plenty of means ‘enough, or more than enough’ and is therefore not likely in certain contexts.
Compare:
- We took lots of food and drink on our walk through the hills. (or …plenty of…) and
- Jim doesn’t look well. He’s lost a lot of weight. (‘plenty of’ is unlikely here)
NOTE 2: Unnaturally, we can use “many, much and a lot of/lots of” in all sentences—questions, positive and negative sentences.
Example:
- Many people are poor in Cambodia.
- She has much time to do everything.
- I don’t have a lot of computers to repair.
- Do you import a lot of cars from the United States?
