---
title: Why do some bats sleep about twenty hours a day? — How animals sleep: half-asleep dolphin… · tree and pragmatics
description: Why do some bats sleep about twenty hours a day? Test 11 of lesson 390 «How animals sleep: half-asleep dolphins, standing horses, short-sleeping giraffes and birds that nap in the air» of the biology course of Mova's primary school, with the dependency tree and pragmatics of the question and of each
---

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# Test 11 · How animals sleep: half-asleep dolphins, standing horses,…

<!-- .ven lang=en -->
Why do some bats sleep about twenty hours a day?

<!-- .vintro -->
**Mova's choice:** option 4 · **The right answer:** option 2 · wrong ✗ · **Who acts:** bats · **What happens:** do, sleep

<!-- .vabout -->
This is test 11 of lesson 390 «How animals sleep: half-asleep dolphins, standing horses, short-sleeping giraffes and birds that nap in the air» of the biology 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/biology/390-how-animals-sleep-half-asleep-dolphins-standing-horses-short-sleeping-giraffes-and-birds-that-nap-in-the-air/#t11).

## The question {#question}

```conllu
# sent_id = question:biology:390-how-animals-sleep-half-asleep-dolphins-standing-horses-short-sleeping-giraffes-and-birds-that-nap-in-the-air:t11:1
# text = Why do some bats sleep about twenty hours a day?
1	Why	why	ADV	WRB	PronType=Int	2	advmod	_	_
2	do	do	VERB	VBP	Mood=Ind|Number=Sing|Person=2|Tense=Pres|VerbForm=Fin	5	advcl	_	_
3	some	some	DET	DT	PronType=Ind	4	det	_	_
4	bats	bat	NOUN	NNS	Number=Plur	5	nsubj	_	_
5	sleep	sleep	VERB	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
6	about	about	ADV	RB	_	7	advmod	_	_
7	twenty	twenty	NUM	CD	NumForm=Word|NumType=Card	8	nummod	_	_
8	hours	hour	NOUN	NNS	Number=Plur	5	obl	_	_
9	a	a	DET	DT	Definite=Ind|PronType=Art	10	det	_	_
10	day	day	NOUN	NN	Number=Sing	8	nmod:unmarked	_	SpaceAfter=No
11	?	?	PUNCT	.	_	5	punct	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **do** | present | some bats *not said here* |  |  |  |  |  | vn act-114-1 «NP V»: agent=Agent |
| 2 | **sleep** | present | some bats |  |  |  | hour |  | vn snooze-40.4-1 «NP V»: 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 -->
They are always cold and stay asleep to keep warm

```conllu
# sent_id = question:biology:390-how-animals-sleep-half-asleep-dolphins-standing-horses-short-sleeping-giraffes-and-birds-that-nap-in-the-air:t11:o1:1
# text = They are always cold and stay asleep to keep warm
1	They	they	PRON	PRP	Case=Nom|Number=Plur|Person=3|PronType=Prs	4	nsubj	_	_
2	are	be	AUX	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	4	cop	_	_
3	always	always	ADV	RB	PronType=Tot	4	advmod	_	_
4	cold	cold	ADJ	JJ	Degree=Pos	0	root	_	_
5	and	and	CCONJ	CC	_	6	cc	_	_
6	stay	stay	VERB	VB	VerbForm=Inf	4	conj	_	_
7	asleep	asleep	ADJ	JJ	Degree=Pos	6	xcomp	_	_
8	to	to	PART	TO	_	9	mark	_	_
9	keep	keep	VERB	VB	VerbForm=Inf	6	advcl	_	_
10	warm	warm	ADJ	JJ	Degree=Pos	9	xcomp	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **is** | present | They |  |  |  |  | always, cold *property* | tree rules |
| 2 | **stay** | infinitive | They *not said here* |  |  |  |  | asleep *property* | vn exist-47.1 «NP V»: agent=Theme |
| 3 | **keep** | to-infinitive | They *not said here* |  |  |  |  | warm *property* | vn keep-15.2 «NP V NP»: agent=Agent |

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

<!-- .ven lang=en -->
They rest when there are no insects to catch

```conllu
# sent_id = question:biology:390-how-animals-sleep-half-asleep-dolphins-standing-horses-short-sleeping-giraffes-and-birds-that-nap-in-the-air:t11:o2:1
# text = They rest when there are no insects to catch
1	They	they	PRON	PRP	Case=Nom|Number=Plur|Person=3|PronType=Prs	2	nsubj	_	_
2	rest	rest	VERB	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
3	when	when	SCONJ	WRB	_	5	mark	_	_
4	there	there	PRON	EX	PronType=Dem	5	expl	_	_
5	are	be	VERB	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	2	ccomp	_	_
6	no	no	DET	DT	PronType=Neg	7	det	_	_
7	insects	insect	NOUN	NNS	Number=Plur	5	nsubj	_	_
8	to	to	PART	TO	_	9	mark	_	_
9	catch	catch	VERB	VB	VerbForm=Inf	2	advcl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **rest** | present | They |  |  |  |  |  | tree rules |
| 2 | **does** | present | no insects |  |  | there |  |  | vn exist-47.1 «NP V»: agent=Theme |
| 3 | **catch** | to-infinitive | They *not said here* |  |  |  |  |  | vn get-13.5.1 «NP V NP»: agent=Agent |

### Option 3 {#o3}

<!-- .ven lang=en -->
They are afraid of the dark

```conllu
# sent_id = question:biology:390-how-animals-sleep-half-asleep-dolphins-standing-horses-short-sleeping-giraffes-and-birds-that-nap-in-the-air:t11:o3:1
# text = They are afraid of the dark
1	They	they	PRON	PRP	Case=Nom|Number=Plur|Person=3|PronType=Prs	3	nsubj	_	_
2	are	be	AUX	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	3	cop	_	_
3	afraid	afraid	ADJ	JJ	Degree=Pos	0	root	_	_
4	of	of	ADP	IN	_	6	case	_	_
5	the	the	DET	DT	Definite=Def|PronType=Art	6	det	_	_
6	dark	dark	NOUN	NN	Number=Sing	3	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **is** | present | They |  |  |  |  | of the dark; afraid *property* | tree rules |

### Option 4 · ← Mova's choice {#o4}

<!-- .ven lang=en -->
They hang upside down for fun

```conllu
# sent_id = question:biology:390-how-animals-sleep-half-asleep-dolphins-standing-horses-short-sleeping-giraffes-and-birds-that-nap-in-the-air:t11:o4:1
# text = They hang upside down for fun
1	They	they	PRON	PRP	Case=Nom|Number=Plur|Person=3|PronType=Prs	2	nsubj	_	_
2	hang	hang	VERB	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
3	upside	upside	NOUN	NN	Number=Sing	2	obj	_	_
4	down	down	ADV	RB	_	2	advmod	_	_
5	for	for	ADP	IN	_	6	case	_	_
6	fun	fun	NOUN	NN	Number=Sing	2	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **hang down** | present | They | upside |  |  |  | for fun; down *property* | vn poison-42.2 «NP V NP»: agent=Agent upside=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.

<!-- /div -->

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- next →: [How animals sleep: half-asleep dolphin…, exam 1](https://md.mova.elamur.ai/free/en/corpora/questions/biology/390-how-animals-sleep-half-asleep-dolphins-standing-horses-short-sleeping-giraffes-and-birds-that-nap-in-the-air/e1/)
- ↑ back to [How animals sleep: half-asleep dolphins, standing horses, short-sleeping giraffes and birds that nap in the air](https://md.mova.elamur.ai/free/en/corpora/questions/biology/390-how-animals-sleep-half-asleep-dolphins-standing-horses-short-sleeping-giraffes-and-birds-that-nap-in-the-air/)