The correct answers are: My suitcase is broken, so I need to buy a new one. Don't pack the dirty shirts; only pack the clean ones.
One correctly replaces the singular noun suitcase, and ones correctly replaces the plural noun shirts.
You cannot use "one" to replace an uncountable noun like water.
"The lighter ones" is incorrect for replacing the singular noun jacket (it should be "the lighter one").
Pronoun
- ✅ between you and me — ❌ between you and I (objective case after preposition)
- ✅ its colour — ❌ it's colour (it's = it is)
- ✅ She did it herself. — reflexive pronoun
- ✅ The person who called… — relative pronoun
Pronouns replace nouns: personal (I/me/my), demonstrative (this/that), relative (who/which/that), interrogative (who?/what?), reflexive (myself), indefinite (everyone/nobody). They carry case that nouns have lost.
Trap: pronouns are where English case still matters: I vs me, who vs whom, its vs it's. Get these wrong and it's instantly noticeable.
Countable and uncountable
- ✅ some advice — ❌ an advice / advices (uncountable → no article, no plural)
- ✅ a piece of furniture — ❌ a furniture / furnitures
- ✅ How much water? — ❌ How many water? (uncountable → much)
- ✅ fewer people — ❌ less people (countable plural → fewer)
English nouns are either countable (take a/an, form plurals, use many/few) or uncountable (no plural, use much/little). The choice is partly arbitrary and must be memorised.
Test: can you put a number in front? Three chairs → countable. Three furnitures ❌ → uncountable. Use a unit phrase instead: three pieces of furniture.
Noun
- The cat sat on the mat. — concrete nouns (things you can touch)
- Happiness is important. — abstract noun (idea/quality)
- London is beautiful. — proper noun (specific name, capitalised)
- I need some information. — uncountable noun (no a/an, no plural)
A noun names a person, place, thing, idea, or quality. Nouns determine article choice, verb agreement, and pronoun reference. Types: common/proper, concrete/abstract, countable/uncountable.
Test: can you put the or a before it? Can you make it plural? If yes to either → it's functioning as a noun.
A2 | Elementary | Pre-intermediate
- ✅ I went to the cinema yesterday. — past simple
- ✅ I have visited Paris twice. — present perfect (life experience)
- ✅ If it rains, I'll take an umbrella. — first conditional
- ✅ You should see a doctor. — modal for advice
These patterns are A2 — the second CEFR level. At A2 you move past survival phrases into real grammar: past tenses, the present perfect, basic conditionals, and modals for advice/obligation.
Marker: if you can describe yesterday and give simple advice, but struggle with abstractions or nuance, you're at A2.
Medium
- If I were you, I would apologise. — one rule (second conditional), but distractors like was tempt you
- Answers require active thought, not instant pattern recognition
- Vocabulary and context are realistic, not artificially simplified
- Usually tests one rule, but the wrong answers are plausible
Medium marks middle-difficulty challenges: A2–B1, one rule tested, but with realistic distractors that require genuine understanding.
Use "Medium" when Easy feels too obvious but Hard feels overwhelming. This is where most productive learning happens — the sweet spot of difficulty.