Olympiad: logic traps and if-then ★★★

Tests: 2 of 11 right · Exam: 1 of 4 right · Kind: ★★★ · Understood: 8 of 15 · Run: 2026-10-18, commit f3c23ea72

Lesson 193 of the world course of Mova's primary school, as Mova's small model took its tests: it had read this lesson and the ones before it and learned from their exercises. Each test shows the options in the order the student saw them, its choice, the right answer, the score of every option and why it chose. The lesson itself, sentence by sentence with trees and pragmatics: the lesson in the corpora.

Every question of this lesson and each of its options parsed by Mova, with trees and pragmatics: the lesson's questions in the corpora.

Test 1 · ★★★ · right ✓

Ethan: "Mate, the rule's 'vowel means even on the back'. I flipped the 4 and there's a K. Rule's broken!" Is he right?

1. Yes; any card at all can break a rule — score 4
2. Yes; a 4 must always have a vowel behind it — no support
3. No; he should have flipped the K instead — no support
4. No; the rule says nothing about what's behind a 4 — ← Mova's choice · ✓ the right answer · score 5

Why: It took the question to ask which statement is true. It chose option 4 with score 5, against 4 for the next best. Its support: lesson 161, line 10: «A rule that explains every result, good or bad, can never be wrong, so it tells you nothing; inventing a new excuse each time it fails is called moving the goa…», reached through the option's own match among the sentences about the question's things. What matched: the same action «tell» (+3); the same thing acted on «nothing» (+2). · the question and its options parsed, with trees and pragmatics

Test 2 · ★★★ · wrong ✗

Ruby from London: "There's no swimming today, bruv, so it's defo Tuesday, innit?" The rule "if Tuesday, then swimming" is always kept. What's true?

1. Every day is a swimming day — ← Mova's choice · no support
2. It is Tuesday — no support
3. It is not Tuesday — ✓ the right answer · no support
4. It might be Tuesday — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 3 · ★★★ · wrong ✗

A man on the island grins: "I am a liar." Ellie: "Sus. That's impossible here." Why is she right?

1. Only truth-tellers can say it, so he must be one — no support
2. Only liars can say it, so he must be one of them — ← Mova's choice · score 5
3. Liars on the island are never allowed to talk — no support
4. A truth-teller can't say it and a liar can't either — ✓ the right answer · no support

Why: It took the question to ask why something happens (its cause). It chose option 2 with score 5, the only option with support. Its support: lesson 193, line 3: «Picture an island where some people always tell the truth and some always lie. Nobody there can ever say "I am a liar": a truth-teller would be lying and a lia…», reached through the same lesson line as the sentence the question matched. What matched: the same action «tell» (+4); the same doer «liar» (+2). Against it: a different thing acted on (counts against) (-1). The right option, 4, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 4 · ★★★ · wrong ✗

Jamie from Newcastle: "Howay, Ann's taller than Ben and Cal's taller than Ben, so Ann's the tallest, the gadgie said." What is true?

1. Ann and Cal are the same height — no support
2. Cal is the tallest — ← Mova's choice · score 5
3. Only that Ben is the shortest — ✓ the right answer · score 5
4. Ann is the tallest — score 5

Why: It took the question to ask which statement is true. It chose option 2 with score 5, tied with another option at 5 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 193, line 4: «Order puzzles need care too: "Ann is taller than Ben, and Cal is taller than Ben" tells you who is shortest, but not who is tallest.», reached through the same lesson line as the sentence the question matched. What matched: the same doer «cal» (+3); the same property (+1); the same light verb (be, have, do, get, go) (+1). The right option, 3, scored 5. · the question and its options parsed, with trees and pragmatics

Test 5 · ★★★ · wrong ✗

Dad: "Not all of you tidied up." Leo: "So none of us tidied, mid effort all round." What did Leo get wrong?

1. "Not all" means exactly half of them tidied — ← Mova's choice · score 4
2. "Not all" means at least one didn't, not that nobody did — ✓ the right answer · score 4
3. Nothing; "not all" means nobody did — no support
4. "Not all" means everyone tidied a bit — score 4

Why: It took the question to ask what it is done to. It chose option 1 with score 4, tied with another option at 4 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 185, line 1: «Small words do big jobs. "All" means every single one, "none" means not one, "some" means at least one, and "not all" means at least one isn't.», reached through a sentence linked to the one the question matched. What matched: the same action «mean» (+2); the same doer «all» (+2). The right option, 2, scored 4. · the question and its options parsed, with trees and pragmatics

Test 6 · ★★★ · wrong ✗

Grandpa from Pittsburgh: "Yinz know some cats are black and some black things are bats, so some cats are bats." What's the best reply?

1. He's right; it follows straight from the two facts given — score 2
2. Only black cats can be bats — ← Mova's choice · score 5
3. Bats can be cats at night only — no support
4. That doesn't follow; they can be different animals — ✓ the right answer · no support

Why: It took the question to ask which statement is true. It chose option 2 with score 5, against 2 for the next best. Its support: lesson 193, line 11: «"Some cats are black and some black things are bats" does not mean some cats are bats; the black cats and the black bats can be different animals.», reached through the remembered sentence the question matched. What matched: the same thing acted on «bats» (+2); the same light verb (be, have, do, get, go) (+2); the same doer «cats» (+1). The right option, 4, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 7 · ★★★ · wrong ✗

Mason: "I've got a ticket and they still didn't let me in! The sign said only ticket holders get in!" What did the sign promise?

1. Only that nobody without a ticket gets in — ✓ the right answer · no support
2. That ticket holders always go to the front — no support
3. That tickets are free — no support
4. That everyone with a ticket gets in — ← Mova's choice · score 9

Why: It took the question to ask what it is done to. It chose option 4 with score 9, the only option with support. Its support: lesson 193, line 12: «"Only people with tickets get in" means anyone who got in had a ticket; it doesn't promise that everyone with a ticket got in.», reached through the remembered sentence the question matched. What matched: the same doer «everyone» (+5); the same action «get in» (+4). The right option, 1, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 8 · ★★★ · right ✓

Lily: "Five heads in a row! Tails is SO due now, it's basically guaranteed." What is true?

1. Each throw is still a half chance of heads — ← Mova's choice · ✓ the right answer · no support
2. Tails is now certain — no support
3. Heads is more likely now, as the coin is on a roll — no support
4. Heads is less likely, since it's had its turn — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 9 · ★★★ · wrong ✗

Mum: "So it's 'not untrue' that you ate the whole cake?" Max: "Technically I didn't say I ate it!" What did Max really admit?

1. That the cake was not true — ← Mova's choice · no support
2. That he didn't eat it — no support
3. That he ate it — ✓ the right answer · no support
4. That he can't remember — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 10 · ★★★ · wrong ✗

Aisha from Glasgow: "Ken what, every bird can fly, no exceptions." Her friend points at a penguin at the zoo. How many such birds does the friend need?

1. Every bird on Earth — ← Mova's choice · score 3
2. At least ten — no support
3. One is enough — ✓ the right answer · no support
4. A thousand — no support

Why: It took the question to ask what it is done to. It chose option 1 with score 3, the only option with support. Its support: lesson 29, line 9: «Penguins are birds: they have feathers and lay hard-shelled eggs, but use their wings as flippers.», reached through the option's own match among the sentences about the question's things. What matched: the same doer «penguins» (+2); it fills the role the question asks for (+1). The right option, 3, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 11 · ★★★ · wrong ✗

Owen, at a fruit stall: "All three labels are wrong? Then I'll have to open all three boxes, obviously." What's the clever way?

1. Take a fruit from the Apples box; that settles it — ← Mova's choice · score 6
2. Take one fruit from the box labelled Mixed — ✓ the right answer · score 6
3. Shake each box and listen — no support
4. Open all three, since a wrong label tells you nothing — no support

Why: It took the question to ask which statement is true. It chose option 1 with score 6, tied with another option at 6 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 193, line 16: «When three boxes are labelled Apples, Oranges and Mixed and every label is wrong, taking one fruit from the box labelled Mixed is enough to put all three label…», reached through the option's own match among the sentences about the question's things. What matched: the same action «take» (+3); the same thing acted on «one fruit» (+2); the same place «box» (+1). The right option, 2, scored 6. · the question and its options parsed, with trees and pragmatics

Exam question 1 · formal language · right ✓

It is given that the proposition "if it is Tuesday, swimming takes place" holds, and that no swimming takes place today. Determine what may be concluded.

1. Today is not Tuesday — ← Mova's choice · ✓ the right answer · no support
2. Today may be Tuesday — no support
3. Nothing may be concluded — no support
4. Today is Tuesday — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Exam question 2 · formal language · wrong ✗

Of four cards showing A, K, 4 and 7, identify those which must be turned in order to test the rule that a vowel on one face implies an even number on the other.

1. A alone — ← Mova's choice · no support
2. A and 4 — no support
3. A, 4 and 7 — no support
4. A and 7 — ✓ the right answer · no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Exam question 3 · formal language · wrong ✗

State the proposition which is the negation of "all the children attended".

1. All the children were absent — ← Mova's choice · no support
2. Some children attended — no support
3. At least one child did not attend — ✓ the right answer · no support
4. No child attended — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Exam question 4 · formal language · wrong ✗

On an island whose inhabitants either always speak truly or always speak falsely, identify the statement which no inhabitant can make.

1. "You are a liar" — ← Mova's choice · no support
2. "I am a liar" — ✓ the right answer · no support
3. "Snow is white" — no support
4. "I speak the truth" — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

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