| Countable | a / an in the singular, -s in the plural | a book / two books |
| Uncountable | masses, materials, ideas: no a / an, no plural | I like music. |
| Verb | a singular verb, also for news | The water is cold. / The news is good. |
| Unit | count it with a unit; the unit takes the plural | a glass of water / a piece of advice / two cups of coffee |
| A2Groups of things | groups of things are uncountable too | furniture / luggage / homework |
| A2Both | some nouns are both; the meaning changes | I like coffee. ≠ Two coffees, please. |
| Trap | advice and information: some, or a piece of | a piece of advice / some advice |
| Trap | work is uncountable; a job is countable | She has a good job. |