We use some before nouns to refer to indefinite quantities. Although the quantity is not important or not defined, using some implies a limited quantity:
Can you get me some milk? (The quantity isn’t specified. Some suggests a normal amount, not an unlimited amount. Compare: Can you get me five litres of milk?)
I’ve got some questions for you.
There are elephants in Africa and Asia. (The number is not limited.)
Not: There are some elephants in Africa and Asia.
Some as a determiner has two forms: a weak form and a strong form. The forms have different meanings.
Weak form some/səm/
We use the weak form of some in affirmative sentences and in questions (usually expecting the answer ‘yes’), when the quantity is indefinite or not important (we use any in questions and negative sentences):
I’ve got some/səm/ water.
Have you got some water? (expecting the answer yes)
Have you got any water? (open yes-no question)
I haven’t got any water. (negative)
We use the weak form of some only with uncountable nouns and plural nouns:
I’m looking for some advice. (+ uncountable noun)
Do you need some help? (+ uncountable noun)
We need to make some changes to the programme. (+ plural noun)
There are a lot of advantages in doing the course online, but there are some disadvantages too. (+ plural noun)
We don’t use weak form some with singular countable nouns:
If you’re looking for a book to read, I can recommend ‘Animal Farm’.
Not: If you’re looking for some book to read …
Strong form some/sʌm/
The strong form of some is stressed. This form contrasts with others or all or enough:
Why do some people live longer than other people? (some, not others)
Some boys went to the front of the stage to get a better view. The rest of us couldn’t see a thing. (some, not all)
There were some cakes left but not enough for everyone. (some, but not enough)
I’m not keen on some types of fish. I find plaice a bit tasteless.
We can use this strong form to refer to someone or something particular but unknown, especially with singular countable nouns:
There must be some way of opening this printer!
Some idiot driver crashed into the back of me.
Some with numbers
We use the strong form of some with numbers. It can suggest an unexpectedly high amount:
Some £30 billion was needed to rebuild the hospital.