---
title: Why does Mercury keep its craters for billions of years? — Mercury · tree and pragmatics
description: Why does Mercury keep its craters for billions of years? Test 7 of lesson 3 «Mercury» of the space course of Mova's primary school, with the dependency tree and pragmatics of the question and of each option; Mova's choice was right.
---

<!-- md -->
[Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/questions/space/3-mercury/t7/)

<!-- 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/) / [Space](https://md.mova.elamur.ai/free/en/corpora/questions/space/) / [Mercury](https://md.mova.elamur.ai/free/en/corpora/questions/space/3-mercury/) / t7

# Test 7 · Mercury

<!-- .ven lang=en -->
Why does Mercury keep its craters for billions of years?

<!-- .vintro -->
**Mova's choice:** option 2 · **The right answer:** option 2 · right ✓ · **Who acts:** Mercury · **What happens:** keep · **To what, where:** craters

<!-- .vabout -->
This is test 7 of lesson 3 «Mercury» of the space 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/space/3-mercury/#t7).

## The question {#question}

```conllu
# sent_id = question:space:3-mercury:t7:1
# text = Why does Mercury keep its craters for billions of years?
1	Why	why	ADV	WRB	PronType=Int	4	advmod	_	_
2	does	do	AUX	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	4	aux	_	_
3	Mercury	Mercury	PROPN	NNP	Number=Sing	4	nsubj	_	_
4	keep	keep	VERB	VB	VerbForm=Inf	0	root	_	_
5	its	its	PRON	PRP$	Case=Gen|Gender=Neut|Number=Sing|Person=3|Poss=Yes|PronType=Prs	6	nmod:poss	_	_
6	craters	crater	NOUN	NNS	Number=Plur	4	obj	_	_
7	for	for	ADP	IN	_	8	case	_	_
8	billions	billion	NOUN	NNS	Number=Plur	4	obl	_	_
9	of	of	ADP	IN	_	10	case	_	_
10	years	year	NOUN	NNS	Number=Plur	8	nmod	_	SpaceAfter=No
11	?	?	PUNCT	.	_	4	punct	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **keep** | present · do-support | Mercury | its craters |  |  |  | for billions of years | vn keep-15.2 «NP V NP»: agent=Agent crater=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 {#o1}

<!-- .ven lang=en -->
Its moons protect them

```conllu
# sent_id = question:space:3-mercury:t7:o1:1
# text = Its moons protect them
1	Its	its	PRON	PRP$	Case=Gen|Gender=Neut|Number=Sing|Person=3|Poss=Yes|PronType=Prs	2	nmod:poss	_	_
2	moons	moon	NOUN	NNS	Number=Plur	3	nsubj	_	_
3	protect	protect	VERB	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
4	them	they	PRON	PRP	Case=Acc|Number=Plur|Person=3|PronType=Prs	3	obj	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **protect** | present | Its moons | them *= they* |  |  |  |  | vn defend-72.3 «NP V NP»: agent=Agent they=Beneficiary |

### Option 2 · ← Mova's choice · ✓ the right answer {#o2}

<!-- .ven lang=en -->
It has no air, rain or moving plates to wear them away

```conllu
# sent_id = question:space:3-mercury:t7:o2:1
# text = It has no air, rain or moving plates to wear them away
1	It	it	PRON	PRP	Case=Nom|Gender=Neut|Number=Sing|Person=3|PronType=Prs	2	nsubj	_	_
2	has	have	VERB	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
3	no	no	DET	DT	PronType=Neg	4	det	_	_
4	air	air	NOUN	NN	Number=Sing	2	obj	_	SpaceAfter=No
5	,	,	PUNCT	,	_	6	punct	_	_
6	rain	rain	NOUN	NN	Number=Sing	4	conj	_	_
7	or	or	CCONJ	CC	_	8	cc	_	_
8	moving	move	VERB	VBG	Tense=Pres|VerbForm=Part	4	conj	_	_
9	plates	plate	NOUN	NNS	Number=Plur	8	obj	_	_
10	to	to	PART	TO	_	11	mark	_	_
11	wear	wear	VERB	VB	VerbForm=Inf	8	advcl	_	_
12	them	they	PRON	PRP	Case=Acc|Number=Plur|Person=3|PronType=Prs	11	obj	_	_
13	away	away	ADV	RB	_	11	advmod	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **have** | present | It | no air and rain |  |  |  |  | vn birth-28.2-1 «NP V NP»: agent=Agent air=Patient |
| 2 | **move** | gerund |  | plates |  |  |  |  | vn roll-51.3.1 «NP V NP.theme»: agent=Agent plate=Theme |
| 3 | **wear away** | to-infinitive |  | plates *= plate* |  |  |  | away *property* | vn wipe\_manner-10.4.1-1 «NP V NP.source»: agent=Agent they=Source |

### Option 3 {#o3}

<!-- .ven lang=en -->
The Sun bakes them hard like pottery in a kiln, so they last

```conllu
# sent_id = question:space:3-mercury:t7:o3:1
# text = The Sun bakes them hard like pottery in a kiln, so they last
1	The	the	DET	DT	Definite=Def|PronType=Art	2	det	_	_
2	Sun	Sun	PROPN	NNP	Number=Sing	3	nsubj	_	_
3	bakes	bake	VERB	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
4	them	they	PRON	PRP	Case=Acc|Number=Plur|Person=3|PronType=Prs	3	obj	_	_
5	hard	hard	ADV	RB	Degree=Pos	3	advmod	_	_
6	like	like	ADP	IN	_	7	case	_	_
7	pottery	pottery	NOUN	NN	Number=Sing	3	obl	_	_
8	in	in	ADP	IN	_	10	case	_	_
9	a	a	DET	DT	Definite=Ind|PronType=Art	10	det	_	_
10	kiln	kiln	NOUN	NN	Number=Sing	3	obl	_	SpaceAfter=No
11	,	,	PUNCT	,	_	14	punct	_	_
12	so	so	ADV	RB	_	14	advmod	_	_
13	they	they	PRON	PRP	Case=Nom|Number=Plur|Person=3|PronType=Prs	14	nsubj	_	_
14	last	last	VERB	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	3	conj	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **bake** | present | the Sun | them *= they* |  |  |  | like pottery; in a kiln; hard *property* | vn cooking-45.3 «NP V NP PP.instrument»: agent=Agent they=Patient in kiln=Instrument |
| 2 | **last** | present | they |  |  |  |  |  | vn cost-54.2 «NP V NP.value»: agent=Theme |

### Option 4 {#o4}

<!-- .ven lang=en -->
Its craters are refilled every year

```conllu
# sent_id = question:space:3-mercury:t7:o4:1
# text = Its craters are refilled every year
1	Its	its	PRON	PRP$	Case=Gen|Gender=Neut|Number=Sing|Person=3|Poss=Yes|PronType=Prs	2	nmod:poss	_	_
2	craters	crater	NOUN	NNS	Number=Plur	4	nsubj	_	_
3	are	be	AUX	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	4	aux:pass	_	_
4	refilled	refill	VERB	VBN	Tense=Past|VerbForm=Part|Voice=Pass	0	root	_	_
5	every	every	DET	DT	PronType=Tot	6	det	_	_
6	year	year	NOUN	NN	Number=Sing	4	obl:unmarked	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **refill** | present · passive |  | Its craters |  |  | year |  | tree rules |

<!-- 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: [Mercury, test 6](https://md.mova.elamur.ai/free/en/corpora/questions/space/3-mercury/t6/)
- next →: [Mercury, test 8](https://md.mova.elamur.ai/free/en/corpora/questions/space/3-mercury/t8/)
- ↑ back to [Mercury](https://md.mova.elamur.ai/free/en/corpora/questions/space/3-mercury/)