Help the mad scientist claim his food in the breakroom! Choose the correct pair of words to complete his demand.
"Excuse me, but that glowing green sandwich is ___," declared the scientist. "Please don't touch ___ lunch!"
The correct answer is mine / my.
Use the possessive pronoun mine when the word stands alone without a noun after it ("the sandwich is mine"). Use the possessive determiner my when it comes directly before a noun to show ownership ("my lunch").
Pronoun
Pronoun vs noun: nouns name explicitly (Sarah, the book). Pronouns substitute and point back (she, it). Pronouns are a closed class (you can't invent new ones easily), while nouns are open (new ones appear constantly). The main complication: pronouns still carry case marking that nouns have lost.
A pronoun replaces a noun or noun phrase. Types: personal, demonstrative, relative, interrogative, reflexive, indefinite.
Diagnostic: every pronoun must have a clear antecedent (the noun it replaces). If the reader can't tell which noun a pronoun refers to → ambiguity error.
Determiner
Determiner vs adjective: both appear before a noun, but determiners specify which/how many while adjectives describe what kind. Determiners come first: the big cat (✅) vs big the cat (❌). You can stack adjectives (big fluffy cat) but generally only one determiner per noun.
A determiner is a function slot before a noun filled by articles, demonstratives, possessives, or quantifiers.
Diagnostic: does the word tell you which one or how many rather than what kind? → determiner. Does it describe a quality? → adjective.
Possessive
Noun possessive vs pronoun possessive: nouns ADD an apostrophe for possession (Sarah's, students'). Pronouns NEVER use apostrophes (its, yours, theirs — no apostrophe). This contradiction is why its/it's is the most common error in English writing.
The possessive marks ownership: 's for singular nouns, s' for plural nouns ending in s, and special pronoun forms (my/mine, their/theirs).
Diagnostic: is it a noun? → add 's or s'. Is it a pronoun? → use the built-in possessive form (NO apostrophe). Specifically its (possessive) vs it's (it is).
A1 | Elementary | Beginners
A1 vs A2: A1 covers isolated survival phrases (Where is…?, I am…, How much?). A2 handles connected sentences about familiar routines and simple past events. If you can manage short fixed phrases but not string together original sentences about your day, you're still A1.
A1 is the entry level of the CEFR: greetings, introductions, numbers, basic present tense, and core function words.
Diagnostic: can you describe yesterday using past tense? No → A1. Yes → you're moving into A2.
Medium
Medium vs Easy: Easy has one obviously correct answer and clearly wrong distractors. Medium has one correct answer but plausible distractors — you need to actually know the rule, not just guess from sound.
The Medium tag filters for A2–B1 challenges with realistic difficulty: one rule per question, plausible alternatives, everyday contexts.
Diagnostic: if you're scoring 90%+ on Easy, move here. If you're below 60% on Medium, go back to Easy for that topic. Target 70–80% accuracy for maximum learning.