---
title: Identify the principal reason for which a large python may subsist f… — The reptile house: snakes · tree and pragmatics
description: Identify the principal reason for which a large python may subsist for months without food. Exam question 1 of lesson 87 «The reptile house: snakes» of the biology course of Mova's primary school, with the dependency tree and pragmatics of the question and of each option; Mova's choice was wrong.
---

<!-- md -->
[Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/questions/biology/87-reptile-house-snakes/e1/)

<!-- crumbs -->
[home](https://md.mova.elamur.ai/free/en/) / [corpora](https://md.mova.elamur.ai/free/en/corpora/) / [questions](https://md.mova.elamur.ai/free/en/corpora/questions/) / [Biology](https://md.mova.elamur.ai/free/en/corpora/questions/biology/) / [The reptile house: snakes](https://md.mova.elamur.ai/free/en/corpora/questions/biology/87-reptile-house-snakes/) / e1

# Exam question 1 · The reptile house: snakes

<!-- .ven lang=en -->
Identify the principal reason for which a large python may subsist for months without food.

<!-- .vintro -->
**Mova's choice:** option 3 · **The right answer:** option 2 · wrong ✗ · **Who acts:** you, large python · **What happens:** identify, subsist · **To what, where:** principal reason

<!-- .vabout -->
This is exam question 1 of lesson 87 «The reptile house: snakes» of the biology 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/biology/87-reptile-house-snakes/#e1).

## The question {#question}

```conllu
# sent_id = question:biology:87-reptile-house-snakes:e1:1
# text = Identify the principal reason for which a large python may subsist for months without food.
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	reason	reason	NOUN	NN	Number=Sing	1	obj	_	_
5	for	for	ADP	IN	_	6	case	_	_
6	which	which	PRON	WDT	PronType=Rel	11	obl	_	_
7	a	a	DET	DT	Definite=Ind|PronType=Art	9	det	_	_
8	large	large	ADJ	JJ	Degree=Pos	9	amod	_	_
9	python	python	NOUN	NN	Number=Sing	11	nsubj	_	_
10	may	may	AUX	MD	VerbForm=Fin	11	aux	_	_
11	subsist	subsist	VERB	VB	VerbForm=Inf	4	acl:relcl	_	_
12	for	for	ADP	IN	_	13	case	_	_
13	months	month	NOUN	NNS	Number=Plur	11	obl	_	_
14	without	without	ADP	IN	_	15	case	_	_
15	food	food	NOUN	NN	Number=Sing	11	obl	_	SpaceAfter=No
16	.	.	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 reason |  |  |  |  | vn characterize-29.2-1-1 «NP V NP S\_ING»: agent=Agent reason=Theme |
| 2 | **subsist** | may | a large python |  |  |  | month | for the principal reason; without food | vn gorge-39.6 «NP V PP.patient»: agent=Agent |

<!-- .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 {#o1}

<!-- .ven lang=en -->
It derives nourishment from water alone

```conllu
# sent_id = question:biology:87-reptile-house-snakes:e1:o1:1
# text = It derives nourishment from water alone
1	It	it	PRON	PRP	Case=Nom|Gender=Neut|Number=Sing|Person=3|PronType=Prs	2	nsubj	_	_
2	derives	derive	VERB	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
3	nourishment	nourishment	NOUN	NN	Number=Sing	2	obj	_	_
4	from	from	ADP	IN	_	5	case	_	_
5	water	water	NOUN	NN	Number=Sing	2	obl	_	_
6	alone	alone	ADV	RB	_	2	advmod	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **derive** | present | It | nourishment |  | water |  | alone *property* | vn create-26.4 «NP V NP PP.material»: agent=Agent nourishment=Result from water=Material |

### Option 2 · ✓ the right answer {#o2}

<!-- .ven lang=en -->
Being cold-blooded, it does not expend food on body heat

```conllu
# sent_id = question:biology:87-reptile-house-snakes:e1:o2:1
# text = Being cold-blooded, it does not expend food on body heat
1	Being	be	AUX	VBG	Tense=Pres|VerbForm=Part	4	cop	_	_
2	cold	cold	ADJ	JJ	Degree=Pos	4	amod	_	SpaceAfter=No
3	-	-	PUNCT	HYPH	_	2	punct	_	SpaceAfter=No
4	blooded	blooded	ADJ	JJ	Degree=Pos	0	root	_	SpaceAfter=No
5	,	,	PUNCT	,	_	9	punct	_	_
6	it	it	PRON	PRP	Case=Nom|Gender=Neut|Number=Sing|Person=3|PronType=Prs	9	nsubj	_	_
7	does	do	AUX	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	9	aux	_	_
8	not	not	PART	RB	Polarity=Neg	9	advmod	_	_
9	expend	expend	VERB	VB	VerbForm=Inf	4	parataxis	_	_
10	food	food	NOUN	NN	Number=Sing	9	obj	_	_
11	on	on	ADP	IN	_	13	case	_	_
12	body	body	NOUN	NN	Number=Sing	13	compound	_	_
13	heat	heat	NOUN	NN	Number=Sing	9	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **is** | gerund |  |  |  |  |  | blooded *property* | tree rules |
| 2 | **not** **expend** | present · do-support | it | food |  | body heat |  |  | tree rules |

### Option 3 · ← Mova's choice {#o3}

<!-- .ven lang=en -->
It consumes small prey continuously and unobserved during the night

```conllu
# sent_id = question:biology:87-reptile-house-snakes:e1:o3:1
# text = It consumes small prey continuously and unobserved during the night
1	It	it	PRON	PRP	Case=Nom|Gender=Neut|Number=Sing|Person=3|PronType=Prs	2	nsubj	_	_
2	consumes	consume	VERB	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
3	small	small	ADJ	JJ	Degree=Pos	4	amod	_	_
4	prey	prey	NOUN	NN	Number=Sing	2	obj	_	_
5	continuously	continuously	ADV	RB	_	2	advmod	_	_
6	and	and	CCONJ	CC	_	7	cc	_	_
7	unobserved	unobserv	VERB	VBN	Tense=Past|VerbForm=Part|Voice=Pass	2	conj	_	_
8	during	during	ADP	IN	_	10	case	_	_
9	the	the	DET	DT	Definite=Def|PronType=Art	10	det	_	_
10	night	night	NOUN	NN	Number=Sing	7	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **consume** | present | It | small prey |  |  |  | continuously *property* | vn consume-66 «NP V NP»: agent=Agent prey=Asset |
| 2 | **unobserv** | participle |  |  |  |  | night |  | tree rules |

### Option 4 {#o4}

<!-- .ven lang=en -->
It absorbs nutrients from the air through its skin

```conllu
# sent_id = question:biology:87-reptile-house-snakes:e1:o4:1
# text = It absorbs nutrients from the air through its skin
1	It	it	PRON	PRP	Case=Nom|Gender=Neut|Number=Sing|Person=3|PronType=Prs	2	nsubj	_	_
2	absorbs	absorb	VERB	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
3	nutrients	nutrient	NOUN	NNS	Number=Plur	2	obj	_	_
4	from	from	ADP	IN	_	6	case	_	_
5	the	the	DET	DT	Definite=Def|PronType=Art	6	det	_	_
6	air	air	NOUN	NN	Number=Sing	2	obl	_	_
7	through	through	ADP	IN	_	9	case	_	_
8	its	its	PRON	PRP$	Case=Gen|Gender=Neut|Number=Sing|Person=3|Poss=Yes|PronType=Prs	9	nmod:poss	_	_
9	skin	skin	NOUN	NN	Number=Sing	2	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **absorb** | present | It | nutrients |  | the air |  | through air's skin | vn absorb-39.8 «NP V NP PP.source»: agent=Goal nutrient=Theme from air=Source |

<!-- div src -->

**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 -->

<!-- pn -->
- ← previous: [The reptile house: snakes, test 12](https://md.mova.elamur.ai/free/en/corpora/questions/biology/87-reptile-house-snakes/t12/)
- next →: [The reptile house: snakes, exam 2](https://md.mova.elamur.ai/free/en/corpora/questions/biology/87-reptile-house-snakes/e2/)
- ↑ back to [The reptile house: snakes](https://md.mova.elamur.ai/free/en/corpora/questions/biology/87-reptile-house-snakes/)