---
title: Why is balancing a pencil on your finger almost impossible? — Balance: the centre of gravity · tree and pragmatics
description: Why is balancing a pencil on your finger almost impossible? Test 9 · ★ of lesson 8 «Balance: the centre of gravity» of the physics course of Mova's primary school, with the dependency tree and pragmatics of the question and of each option; Mova's choice was right.
---

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# Test 9 · ★ · Balance: the centre of gravity

<!-- .ven lang=en -->
Why is balancing a pencil on your finger almost impossible?

<!-- .vintro -->
**Mova's choice:** option 1 · **The right answer:** option 1 · right ✓ · **What happens:** balance · **To what, where:** pencil, finger

<!-- .vabout -->
This is test 9 · ★ of lesson 8 «Balance: the centre of gravity» of the physics course of Mova's primary school. 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/physics/8-balance-the-centre-of-gravity/#t9).

## The question {#question}

```conllu
# sent_id = question:physics:8-balance-the-centre-of-gravity:t9:1
# text = Why is balancing a pencil on your finger almost impossible?
1	Why	why	ADV	WRB	PronType=Int	3	advmod	_	_
2	is	be	AUX	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	3	aux	_	_
3	balancing	balance	VERB	VBG	Tense=Pres|VerbForm=Part	0	root	_	_
4	a	a	DET	DT	Definite=Ind|PronType=Art	5	det	_	_
5	pencil	pencil	NOUN	NN	Number=Sing	3	obj	_	_
6	on	on	ADP	IN	_	8	case	_	_
7	your	your	PRON	PRP$	Case=Gen|Person=2|Poss=Yes|PronType=Prs	8	nmod:poss	_	_
8	finger	finger	NOUN	NN	Number=Sing	3	obl	_	_
9	almost	almost	ADV	RB	_	10	advmod	_	_
10	impossible	impossible	ADJ	JJ	Degree=Pos	8	amod	_	SpaceAfter=No
11	?	?	PUNCT	.	_	3	punct	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **balance** | present · progressive |  | a pencil |  | your finger |  |  | vn spatial\_configuration-47.6-1 «NP V NP.theme PP»: agent=Agent pencil=Theme on finger=Location |

<!-- .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 -->
It tips over too fast to correct

```conllu
# sent_id = question:physics:8-balance-the-centre-of-gravity:t9:o1:1
# text = It tips over too fast to correct
1	It	it	PRON	PRP	Case=Nom|Gender=Neut|Number=Sing|Person=3|PronType=Prs	2	nsubj	_	_
2	tips	tip	VERB	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
3	over	over	ADP	RP	_	2	compound:prt	_	_
4	too	too	ADV	RB	_	5	advmod	_	_
5	fast	fast	ADV	RB	Degree=Pos	2	advmod	_	_
6	to	to	PART	TO	_	7	mark	_	_
7	correct	correct	VERB	VB	VerbForm=Inf	5	advcl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **tip over** | present | It |  |  |  |  | fast *property* | vn throw-17.1-1-1 «NP V NP»: agent=Agent |
| 2 | **correct** *speech: disagree* | to-infinitive |  |  |  |  |  |  | vn remedy-45.7 «NP V NP.patient»: agent=Agent |

### Option 2 {#o2}

<!-- .ven lang=en -->
It is too long and thin to see

```conllu
# sent_id = question:physics:8-balance-the-centre-of-gravity:t9:o2:1
# text = It is too long and thin to see
1	It	it	PRON	PRP	Case=Nom|Gender=Neut|Number=Sing|Person=3|PronType=Prs	4	nsubj	_	_
2	is	be	AUX	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	4	cop	_	_
3	too	too	ADV	RB	_	4	advmod	_	_
4	long	long	ADJ	JJ	Degree=Pos	0	root	_	_
5	and	and	CCONJ	CC	_	6	cc	_	_
6	thin	thin	ADJ	JJ	Degree=Pos	4	conj	_	_
7	to	to	PART	TO	_	8	mark	_	_
8	see	see	VERB	VB	VerbForm=Inf	6	advcl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **is** | present | It |  |  |  |  | long *property* | tree rules |
| 2 | **be** |  |  |  |  |  |  |  | tree rules |
| 3 | **see** | to-infinitive |  |  |  |  |  |  | vn comprehend-87.2-1-1 «NP V»: agent=Experiencer |

### Option 3 {#o3}

<!-- .ven lang=en -->
It is far too heavy

```conllu
# sent_id = question:physics:8-balance-the-centre-of-gravity:t9:o3:1
# text = It is far too heavy
1	It	it	PRON	PRP	Case=Nom|Gender=Neut|Number=Sing|Person=3|PronType=Prs	5	nsubj	_	_
2	is	be	AUX	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	5	cop	_	_
3	far	far	ADV	RB	Degree=Pos	5	advmod	_	_
4	too	too	ADV	RB	_	5	advmod	_	_
5	heavy	heavy	ADJ	JJ	Degree=Pos	0	root	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **is** | present | It |  |  |  |  | far, heavy *property* | tree rules |

### Option 4 {#o4}

<!-- .ven lang=en -->
Pencils have no centre of gravity

```conllu
# sent_id = question:physics:8-balance-the-centre-of-gravity:t9:o4:1
# text = Pencils have no centre of gravity
1	Pencils	pencil	NOUN	NNS	Number=Plur	2	nsubj	_	_
2	have	have	VERB	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
3	no	no	DET	DT	PronType=Neg	4	det	_	_
4	centre	centre	NOUN	NN	Number=Sing	2	obj	_	_
5	of	of	ADP	IN	_	6	case	_	_
6	gravity	gravity	NOUN	NN	Number=Sing	4	nmod	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **have** | present | Pencils | no centre of gravity |  |  |  |  | vn birth-28.2-1 «NP V NP»: agent=Agent centre=Patient |

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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.

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- ← previous: [Balance: the centre of gravity, test 8](https://md.mova.elamur.ai/free/en/corpora/questions/physics/8-balance-the-centre-of-gravity/t8/)
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