---
title: Identify the minimum number of counterexamples required to demonstra… — One counterexample is enough · tree and pragmatics
description: Identify the minimum number of counterexamples required to demonstrate that a claim concerning all members of a group is false. Exam question 1 of lesson 187 «One counterexample is enough» of the world course of Mova's primary school, with the dependency tree and pragmatics of the question and of ea
---

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# Exam question 1 · One counterexample is enough

<!-- .ven lang=en -->
Identify the minimum number of counterexamples required to demonstrate that a claim concerning all members of a group is false.

<!-- .vintro -->
**Mova's choice:** option 1 · **The right answer:** option 1 · right ✓ · **Who acts:** you, claim · **What happens:** identify, require, demonstrate, concern, be · **To what, where:** minimum number, counterexamples, members

<!-- .vabout -->
This is exam question 1 of lesson 187 «One counterexample is enough» of the world course of Mova's primary school, asked in stiff, formal language. The page gives the question's syntax tree — a dependency tree in the style of Universal Dependencies — and its pragmatics clause by clause, then the 4 options as the student saw them, each with its tree and pragmatics. Every text is parsed by Mova itself. How the student answered it, with the score of every option and why: [the test at school](https://md.mova.elamur.ai/free/en/school-run/world/187-one-counterexample-is-enough/#e1).

## The question {#question}

```conllu
# sent_id = question:world:187-one-counterexample-is-enough:e1:1
# text = Identify the minimum number of counterexamples required to demonstrate that a claim concerning all members of a group is false.
1	Identify	identify	VERB	VB	Mood=Imp|VerbForm=Fin	0	root	_	_
2	the	the	DET	DT	Definite=Def|PronType=Art	4	det	_	_
3	minimum	minimum	ADJ	JJ	Degree=Pos	4	amod	_	_
4	number	number	NOUN	NN	Number=Sing	1	obj	_	_
5	of	of	ADP	IN	_	6	case	_	_
6	counterexamples	counterexample	NOUN	NNS	Number=Plur	4	nmod	_	_
7	required	require	VERB	VBN	Tense=Past|VerbForm=Part|Voice=Pass	6	acl	_	_
8	to	to	PART	TO	_	9	mark	_	_
9	demonstrate	demonstrate	VERB	VB	VerbForm=Inf	7	xcomp	_	_
10	that	that	SCONJ	IN	_	20	mark	_	_
11	a	a	DET	DT	Definite=Ind|PronType=Art	12	det	_	_
12	claim	claim	NOUN	NN	Number=Sing	20	nsubj	_	_
13	concerning	concern	VERB	VBG	VerbForm=Ger	12	acl	_	_
14	all	all	DET	DT	PronType=Tot	15	det	_	_
15	members	member	NOUN	NNS	Number=Plur	13	obj	_	_
16	of	of	ADP	IN	_	18	case	_	_
17	a	a	DET	DT	Definite=Ind|PronType=Art	18	det	_	_
18	group	group	NOUN	NN	Number=Sing	15	nmod	_	_
19	is	be	AUX	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	20	cop	_	_
20	false	false	ADJ	JJ	Degree=Pos	9	advcl	_	SpaceAfter=No
21	.	.	PUNCT	.	_	1	punct	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **identify** | imperative | you *not said here* | the minimum number of counterexamples |  |  |  |  | vn characterize-29.2-1-1 «NP V NP S\_ING»: agent=Agent number=Theme |
| 2 | **require** | participle |  | counterexamples *not said here* |  |  |  |  | vn require-103-1 «NP V NP S\_INF»: agent=Theme clause=Precondition |
| 3 | **demonstrate** | to-infinitive |  |  |  |  |  |  | vn transfer\_mesg-37.1.1 «NP V»: agent=Agent |
| 4 | **concern** | gerund | a claim *not said here* | all members of a group |  |  |  |  | vn amuse-31.1 «NP V NP»: agent=Stimulus member=Experiencer |
| 5 | **is** | present | a claim |  |  |  |  | false *property* | tree rules |

<!-- .note -->
One row per clause the reader finds. «not said here»: a role filled from the clause above. «roles by»: a VerbNet class and frame when one fits the verb, else the reader's rules on the tree.

## The options {#options}

### Option 1 · ← Mova's choice · ✓ the right answer {#o1}

<!-- .ven lang=en -->
One

```conllu
# sent_id = question:world:187-one-counterexample-is-enough:e1:o1:1
# text = One
1	One	one	NUM	CD	NumForm=Word|NumType=Card	0	root	_	_
```

<!-- .note -->
The frames reader finds no event or fact in this sentence.

### Option 2 {#o2}

<!-- .ven lang=en -->
Two

```conllu
# sent_id = question:world:187-one-counterexample-is-enough:e1:o2:1
# text = Two
1	Two	two	NUM	CD	NumForm=Word|NumType=Card	0	root	_	_
```

<!-- .note -->
The frames reader finds no event or fact in this sentence.

### Option 3 {#o3}

<!-- .ven lang=en -->
All members of the group

```conllu
# sent_id = question:world:187-one-counterexample-is-enough:e1:o3:1
# text = All members of the group
1	All	all	DET	DT	PronType=Tot	2	det	_	_
2	members	member	NOUN	NNS	Number=Plur	0	root	_	_
3	of	of	ADP	IN	_	5	case	_	_
4	the	the	DET	DT	Definite=Def|PronType=Art	5	det	_	_
5	group	group	NOUN	NN	Number=Sing	2	nmod	_	_
```

<!-- .note -->
The frames reader finds no event or fact in this sentence.

### Option 4 {#o4}

<!-- .ven lang=en -->
Ten

```conllu
# sent_id = question:world:187-one-counterexample-is-enough:e1:o4:1
# text = Ten
1	Ten	ten	NUM	CD	NumForm=Word|NumType=Card	0	root	_	_
```

<!-- .note -->
The frames reader finds no event or fact in this sentence.

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**Text:** the tests of Mova's primary school, written for Mova (`world/data/school/`), as the course runner gave them to the student. **Trees:** Mova's own parse — the `en` model on the CPU, when the site is built — not checked by a teacher; they may be wrong. **Frames:** Mova's frames reader (`prag`), each text read on its own. Elamur Cosmic License.

<!-- /div -->

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- ← previous: [One counterexample is enough, test 12](https://md.mova.elamur.ai/free/en/corpora/questions/world/187-one-counterexample-is-enough/t12/)
- next →: [One counterexample is enough, exam 2](https://md.mova.elamur.ai/free/en/corpora/questions/world/187-one-counterexample-is-enough/e2/)
- ↑ back to [One counterexample is enough](https://md.mova.elamur.ai/free/en/corpora/questions/world/187-one-counterexample-is-enough/)