Вопрос по английскому языку:

5 look at the sentences and complete the rules with some, any or a/an. Give examples from exercise 4.
a. We use_____ with singular countable nouns.
b. We use_____with countable and uncountable nouns in positives.
c. We use_____ with countable and uncountable nouns in negatives.
помогите пожалуйста. Срочно