Essential Rules for English Modals and Noun Classification

Posted on Nov 16, 2025 in English

Modals Expressing Certainty and Speculation

1. We use modals and modal-like expressions to express different degrees of certainty.
2. Use must / have got to + base form when you are not speculating about the present. (FALSE)
3. To make a negative speculation (deduction), use can’t / couldn’t + base form.
4. Use must not + base form when you are slightly more certain. (FALSE)
5. In questions, use could / couldn’t + base form.
6. Use may / might / could + base form when you are speculating about the present and are less certain.
7. Use may not / might not + base form in the negative.
8. In questions, use could / might + base form.
9. Use must have / had to have + past participle when you are speculating about the past and are almost certain.
10. In the positive, use can’t have / couldn’t have + past participle to suggest impossibility. (FALSE)
11. Use must not have + past participle when you are slightly less certain. (FALSE)
12. In questions, use can have / could have + past participle. (FALSE)
13. When you are speculating about the past and are less certain (about 50%), use may have / might have.
14. Could have + past participle has two meanings. (FALSE)
15. In the negative and positive, use may not have / might not have + past participle.
16. In questions and answers, use might have / could have + past participle.
17. Use should / ought to + base form when you are almost certain about a future action or event (expectation).
18. Use may / might / could + base form when you are speculating about a future action or event.
19. In the negative, use may / might + not / never + base form.

Classification and Usage of Nouns

General Noun Types

20. There are two types of nouns: proper nouns and common nouns.
21. There are two types of common nouns: count nouns and non-count nouns.
22. Nouns name people, places, and things.
23. Proper nouns name particular people, places, or things.
24. Proper nouns are usually unique and are capitalized in writing.
25. Common nouns refer to people, places, or things but are not names of particular individuals.

Count Nouns

26. Count nouns refer to things that you can count separately.
27. Count nouns can be singular or plural.
28. You can use a or an before count nouns.

Non-Count Nouns

29. Non-count nouns refer to things that you cannot count separately.
30. Non-count nouns usually have no plural.
31. We usually do not use a or an with non-count nouns, though they are often preceded by some or the.
32. We normally use a singular verb with a non-count noun.
33. We use a singular pronoun to refer to the noun.
34. Categories of non-count nouns include: abstractions, diseases, and particles.

Count and Non-Count Usage

35. Many nouns have both a non-count and a count meaning.
36. We can make certain non-count nouns countable by adding a phrase that gives them form, a limit, or a container.
37. We can use many non-count nouns in a countable sense with a / an or in the plural to mean kind / type / variety of.
38. A / an and plurals can also be used to indicate discrete amounts.
39. Rice and nutrition are count nouns. (FALSE)
40. A, one, and two are non-count nouns. (FALSE)