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2026 · open round · B · 10 points

Game: Set Match

Tom McCoy · semantics · formal and computational

Consider the word walruses and the phrase cheerful walruses. The diagram below shows one way to illustrate the relationship between these phrases.

A large circle labelled walruses. Fully inside it sits a smaller circle labelled cheerful walruses.

Each circle stands for the set of things that could be described by the relevant word or phrase. Since all cheerful walruses are walruses, the region for cheerful walruses is fully contained inside the region for walruses. The sizes of the circles are irrelevant; what matters is how they overlap and which ones are contained inside others.

This example relates to an important question: how does the meaning of a phrase relate to the meanings of the words that make it up? This question comes up in computational linguistics because computers that process language must be able to determine the meanings of complex phrases.

Note that this problem only gives a partial picture of meaning in language. Some nuances that are left out are important in linguistic theories, but for the sake of this problem you should only use the information presented.

Below are 18 words and phrases in arbitrary order, along with a diagram representing their meanings.

LabelPhraseLabelPhraseLabelPhrase
Aalleged spiesGfruitsMpurple Italian cars
BberriesHfuture spiesNsmall big elephants
Cbig elephantsIgreen carsOsmall blueberries
DblueberriesJgreen Italian carsPsmall elephants
EcarsKhappy spiesQspies
FelephantsLItalian carsRstrawberries
Four separate groups of overlapping and nested circles. Each region carries a number from 1 to 18 in a small box touching its circle.
Each number goes with the circle it touches, except for 8, which goes with the intersection of the 7 and 10 circles.

Notes. Alleged spies are people who have been accused of being spies but who may or may not actually be spies. The phrase small big elephants may be confusing without context; here is an example where it can occur: “That’s a big elephant, but compared to other big elephants it’s relatively small; it’s a small big elephant.” We assume that cars cannot be both green and purple at the same time. We use the informal definition of berry, in which strawberries are a type of berry. We assume that elephants cannot be spies.

TimerOptional. Set whatever limit suits you.

Questions

0 of 18 correct
B1

Each of the words or phrases A–R corresponds to one of the regions 1–18 in the diagram. Enter the letter for each region.

Region 1
Region 2
Region 3
Region 4
Region 5
Region 6
Region 7
Region 8
Region 9
Region 10
Region 11
Region 12
Region 13
Region 14
Region 15
Region 16
Region 17
Region 18

Explanation

Try the questions first. Use the Hint button next to any part if you need a nudge.

Reading the explanation costs no XP. Worth 10 points in the real exam.