---
title: Identify the principal function of the crystalline lens of the human… — Lenses and eyes · tree and pragmatics
description: Identify the principal function of the crystalline lens of the human eye. Exam question 1 of lesson 22 «Lenses and eyes» 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 wrong.
---

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# Exam question 1 · Lenses and eyes

<!-- .ven lang=en -->
Identify the principal function of the crystalline lens of the human eye.

<!-- .vintro -->
**Mova's choice:** option 1 · **The right answer:** option 3 · wrong ✗ · **Who acts:** you · **What happens:** identify · **To what, where:** principal function

<!-- .vabout -->
This is exam question 1 of lesson 22 «Lenses and eyes» of the physics 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/physics/22-lenses-and-eyes/#e1).

## The question {#question}

```conllu
# sent_id = question:physics:22-lenses-and-eyes:e1:1
# text = Identify the principal function of the crystalline lens of the human eye.
1	Identify	identify	VERB	VB	Mood=Imp|VerbForm=Fin	0	root	_	_
2	the	the	DET	DT	Definite=Def|PronType=Art	4	det	_	_
3	principal	principal	ADJ	JJ	Degree=Pos	4	amod	_	_
4	function	function	NOUN	NN	Number=Sing	1	obj	_	_
5	of	of	ADP	IN	_	8	case	_	_
6	the	the	DET	DT	Definite=Def|PronType=Art	8	det	_	_
7	crystalline	crystalline	ADJ	JJ	Degree=Pos	8	amod	_	_
8	lens	lens	NOUN	NN	Number=Sing	4	nmod	_	_
9	of	of	ADP	IN	_	12	case	_	_
10	the	the	DET	DT	Definite=Def|PronType=Art	12	det	_	_
11	human	human	ADJ	JJ	Degree=Pos	12	amod	_	_
12	eye	eye	NOUN	NN	Number=Sing	8	nmod	_	SpaceAfter=No
13	.	.	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 principal function of the crystalline lens of the human eye |  |  |  |  | vn characterize-29.2-1-1 «NP V NP S\_ING»: agent=Agent function=Theme |

<!-- .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 {#o1}

<!-- .ven lang=en -->
To exclude particles of dust from the eye

```conllu
# sent_id = question:physics:22-lenses-and-eyes:e1:o1:1
# text = To exclude particles of dust from the eye
1	To	to	PART	TO	_	2	mark	_	_
2	exclude	exclude	VERB	VB	Mood=Imp|VerbForm=Fin	0	root	_	_
3	particles	particle	NOUN	NNS	Number=Plur	2	obj	_	_
4	of	of	ADP	IN	_	5	case	_	_
5	dust	dust	NOUN	NN	Number=Sing	3	nmod	_	_
6	from	from	ADP	IN	_	8	case	_	_
7	the	the	DET	DT	Definite=Def|PronType=Art	8	det	_	_
8	eye	eye	NOUN	NN	Number=Sing	2	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **exclude** | to-infinitive |  | particles of dust |  | the eye |  |  | vn forbid-64.4-1 «NP V NP PP.theme»: agent=Causer particle=Beneficiary from eye=Eventuality |

### Option 2 {#o2}

<!-- .ven lang=en -->
To store visual images for subsequent recall

```conllu
# sent_id = question:physics:22-lenses-and-eyes:e1:o2:1
# text = To store visual images for subsequent recall
1	To	to	PART	TO	_	2	mark	_	_
2	store	store	VERB	VB	Mood=Imp|VerbForm=Fin	0	root	_	_
3	visual	visual	ADJ	JJ	Degree=Pos	4	amod	_	_
4	images	image	NOUN	NNS	Number=Plur	2	obj	_	_
5	for	for	ADP	IN	_	7	case	_	_
6	subsequent	subsequent	ADJ	JJ	Degree=Pos	7	amod	_	_
7	recall	recall	NOUN	NN	Number=Sing	2	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **store** | to-infinitive |  | visual images |  |  |  | for subsequent recall | vn keep-15.2 «NP V NP»: agent=Agent image=Theme |

### Option 3 · ✓ the right answer {#o3}

<!-- .ven lang=en -->
To refract light so as to form a focused image upon the retina

```conllu
# sent_id = question:physics:22-lenses-and-eyes:e1:o3:1
# text = To refract light so as to form a focused image upon the retina
1	To	to	PART	TO	_	2	mark	_	_
2	refract	refract	VERB	VB	VerbForm=Inf	7	advcl	_	_
3	light	light	NOUN	NN	Number=Sing	2	obj	_	_
4	so	so	ADV	RB	_	7	advmod	_	_
5	as	as	SCONJ	IN	_	7	mark	_	_
6	to	to	PART	TO	_	7	mark	_	_
7	form	form	VERB	VB	Mood=Imp|VerbForm=Fin	0	root	_	_
8	a	a	DET	DT	Definite=Ind|PronType=Art	10	det	_	_
9	focused	focused	ADJ	JJ	Degree=Pos	10	amod	_	_
10	image	image	NOUN	NN	Number=Sing	7	obj	_	_
11	upon	upon	ADP	IN	_	13	case	_	_
12	the	the	DET	DT	Definite=Def|PronType=Art	13	det	_	_
13	retina	retina	NOUN	NN	Number=Sing	7	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **refract** | to-infinitive |  | light |  |  |  |  | vn remedy-45.7 «NP V NP.patient»: agent=Agent light=Patient |
| 2 | **form** | to-infinitive |  | a focused image |  |  |  | upon the retina | vn appear-48.1.1 «PP.location V NP»: agent=Location image=Theme |

### Option 4 {#o4}

<!-- .ven lang=en -->
To emit light whereby the objects before the eye are illuminated at night

```conllu
# sent_id = question:physics:22-lenses-and-eyes:e1:o4:1
# text = To emit light whereby the objects before the eye are illuminated at night
1	To	to	PART	TO	_	2	mark	_	_
2	emit	emit	VERB	VB	Mood=Imp|VerbForm=Fin	0	root	_	_
3	light	light	NOUN	NN	Number=Sing	2	obj	_	_
4	whereby	whereby	ADV	WRB	PronType=Int	11	advmod	_	_
5	the	the	DET	DT	Definite=Def|PronType=Art	6	det	_	_
6	objects	object	NOUN	NNS	Number=Plur	11	nsubj:pass	_	_
7	before	before	ADP	IN	_	9	case	_	_
8	the	the	DET	DT	Definite=Def|PronType=Art	9	det	_	_
9	eye	eye	NOUN	NN	Number=Sing	6	nmod	_	_
10	are	be	AUX	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	11	aux:pass	_	_
11	illuminated	illuminate	VERB	VBN	Tense=Past|VerbForm=Part|Voice=Pass	2	advcl	_	_
12	at	at	ADP	IN	_	13	case	_	_
13	night	night	NOUN	NN	Number=Sing	11	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **emit** | to-infinitive |  | light |  |  |  |  | vn substance\_emission-43.4 «NP V NP»: agent=Source light=Theme |
| 2 | **illuminate** | present · passive |  | the objects before the eye |  |  | night | whereby *property* | vn illustrate-25.3 «NP V NP»: subject=Destination |

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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: [Lenses and eyes, test 10](https://md.mova.elamur.ai/free/en/corpora/questions/physics/22-lenses-and-eyes/t10/)
- next →: [Lenses and eyes, exam 2](https://md.mova.elamur.ai/free/en/corpora/questions/physics/22-lenses-and-eyes/e2/)
- ↑ back to [Lenses and eyes](https://md.mova.elamur.ai/free/en/corpora/questions/physics/22-lenses-and-eyes/)