---
title: Ascertain the reason for which the Okavango Delta is inundated durin… — Great rivers and wetlands: Nile crocod… · tree and pragmatics
description: Ascertain the reason for which the Okavango Delta is inundated during the dry season. Exam question 3 of lesson 184 «Great rivers and wetlands: Nile crocodiles, hippos, giant catfish and the Pantanal» of the biology course of Mova's primary school, with the dependency tree and pragmatics of the ques
---

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# Exam question 3 · Great rivers and wetlands: Nile crocodiles, hippos, giant…

<!-- .ven lang=en -->
Ascertain the reason for which the Okavango Delta is inundated during the dry season.

<!-- .vintro -->
**Mova's choice:** option 2 · **The right answer:** option 2 · right ✓ · **Who acts:** you · **What happens:** ascertain, inundate · **To what, where:** reason, Okavango Delta

<!-- .vabout -->
This is exam question 3 of lesson 184 «Great rivers and wetlands: Nile crocodiles, hippos, giant catfish and the Pantanal» 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/184-great-rivers-and-wetlands-nile-crocodiles-hippos-giant-catfish-and-the-pantanal/#e3).

## The question {#question}

```conllu
# sent_id = question:biology:184-great-rivers-and-wetlands-nile-crocodiles-hippos-giant-catfish-and-the-pantanal:e3:1
# text = Ascertain the reason for which the Okavango Delta is inundated during the dry season.
1	Ascertain	ascertain	VERB	VB	Mood=Imp|VerbForm=Fin	0	root	_	_
2	the	the	DET	DT	Definite=Def|PronType=Art	3	det	_	_
3	reason	reason	NOUN	NN	Number=Sing	1	obj	_	_
4	for	for	ADP	IN	_	5	case	_	_
5	which	which	PRON	WDT	PronType=Rel	10	obl	_	_
6	the	the	DET	DT	Definite=Def|PronType=Art	8	det	_	_
7	Okavango	Okavango	PROPN	NNP	Number=Sing	8	compound	_	_
8	Delta	Delta	PROPN	NNP	Number=Sing	10	nsubj	_	_
9	is	be	AUX	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	10	aux:pass	_	_
10	inundated	inundate	VERB	VBN	Tense=Past|VerbForm=Part|Voice=Pass	3	acl:relcl	_	_
11	during	during	ADP	IN	_	14	case	_	_
12	the	the	DET	DT	Definite=Def|PronType=Art	14	det	_	_
13	dry	dry	ADJ	JJ	Degree=Pos	14	amod	_	_
14	season	season	NOUN	NN	Number=Sing	10	obl	_	SpaceAfter=No
15	.	.	PUNCT	.	_	1	punct	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **ascertain** | imperative | you *not said here* | the reason |  |  |  |  | vn discover-84 «NP V NP»: agent=Agent reason=Topic |
| 2 | **inundate** | present · passive |  | the Okavango Delta |  |  | season | for the reason | vn fill-9.8 «NP V NP»: subject=Destination |

<!-- .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 -->
Rainfall occurs there exclusively in the dry season

```conllu
# sent_id = question:biology:184-great-rivers-and-wetlands-nile-crocodiles-hippos-giant-catfish-and-the-pantanal:e3:o1:1
# text = Rainfall occurs there exclusively in the dry season
1	Rainfall	rainfall	NOUN	NN	Number=Sing	2	nsubj	_	_
2	occurs	occur	VERB	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
3	there	there	ADV	RB	PronType=Dem	2	advmod	_	_
4	exclusively	exclusively	ADV	RB	_	2	advmod	_	_
5	in	in	ADP	IN	_	8	case	_	_
6	the	the	DET	DT	Definite=Def|PronType=Art	8	det	_	_
7	dry	dry	ADJ	JJ	Degree=Pos	8	amod	_	_
8	season	season	NOUN	NN	Number=Sing	2	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **occur** | present | Rainfall |  |  | there | season | exclusively *property* | vn occur-48.3-1 «NP V»: agent=Theme |

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

<!-- .ven lang=en -->
Precipitation falling at a great distance requires months to flow down to the delta

```conllu
# sent_id = question:biology:184-great-rivers-and-wetlands-nile-crocodiles-hippos-giant-catfish-and-the-pantanal:e3:o2:1
# text = Precipitation falling at a great distance requires months to flow down to the delta
1	Precipitation	precipitation	NOUN	NN	Number=Sing	7	nsubj	_	_
2	falling	fall	VERB	VBG	VerbForm=Ger	1	acl	_	_
3	at	at	ADP	IN	_	6	case	_	_
4	a	a	DET	DT	Definite=Ind|PronType=Art	6	det	_	_
5	great	great	ADJ	JJ	Degree=Pos	6	amod	_	_
6	distance	distance	NOUN	NN	Number=Sing	2	obl	_	_
7	requires	require	VERB	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
8	months	month	NOUN	NNS	Number=Plur	7	obj	_	_
9	to	to	PART	TO	_	10	mark	_	_
10	flow	flow	VERB	VB	VerbForm=Inf	7	xcomp	_	_
11	down	down	ADV	RB	_	10	advmod	_	_
12	to	to	ADP	IN	_	14	case	_	_
13	the	the	DET	DT	Definite=Def|PronType=Art	14	det	_	_
14	delta	delta	NOUN	NN	Number=Sing	10	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **fall** | gerund | Precipitation *not said here* |  |  |  |  | at a great distance | vn occur-48.3 «NP V PP»: agent=Theme at distance=Location |
| 2 | **require** | present | Precipitation |  |  |  | month |  | vn require-103-1 «NP V NP S\_INF»: agent=Theme clause=Precondition |
| 3 | **flow down** | to-infinitive | Precipitation *not said here* |  |  |  |  | to the delta; down *property* | vn appear-48.1.1 «NP V»: agent=Theme |

### Option 3 {#o3}

<!-- .ven lang=en -->
Sea water enters the delta from the coast

```conllu
# sent_id = question:biology:184-great-rivers-and-wetlands-nile-crocodiles-hippos-giant-catfish-and-the-pantanal:e3:o3:1
# text = Sea water enters the delta from the coast
1	Sea	sea	NOUN	NN	Number=Sing	2	compound	_	_
2	water	water	NOUN	NN	Number=Sing	3	nsubj	_	_
3	enters	enter	VERB	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
4	the	the	DET	DT	Definite=Def|PronType=Art	5	det	_	_
5	delta	delta	NOUN	NN	Number=Sing	3	obj	_	_
6	from	from	ADP	IN	_	8	case	_	_
7	the	the	DET	DT	Definite=Def|PronType=Art	8	det	_	_
8	coast	coast	NOUN	NN	Number=Sing	3	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **enter** | present | Sea water | the delta |  | the coast |  |  | vn escape-51.1-1-2 «NP V NP»: agent=Theme delta=Destination |

### Option 4 {#o4}

<!-- .ven lang=en -->
The flood is caused by melting snow upon the delta

```conllu
# sent_id = question:biology:184-great-rivers-and-wetlands-nile-crocodiles-hippos-giant-catfish-and-the-pantanal:e3:o4:1
# text = The flood is caused by melting snow upon the delta
1	The	the	DET	DT	Definite=Def|PronType=Art	2	det	_	_
2	flood	flood	NOUN	NN	Number=Sing	4	nsubj	_	_
3	is	be	AUX	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	4	aux:pass	_	_
4	caused	cause	VERB	VBN	Tense=Past|VerbForm=Part|Voice=Pass	0	root	_	_
5	by	by	SCONJ	IN	_	6	mark	_	_
6	melting	melt	VERB	VBG	Tense=Pres|VerbForm=Part	4	advcl	_	_
7	snow	snow	NOUN	NN	Number=Sing	6	obj	_	_
8	upon	upon	ADP	IN	_	10	case	_	_
9	the	the	DET	DT	Definite=Def|PronType=Art	10	det	_	_
10	delta	delta	NOUN	NN	Number=Sing	6	obl	_	_
```

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **cause** | present · passive |  | the flood |  |  |  |  | vn engender-27.1-1 «NP V NP»: subject=Patient |
| 2 | **melt** | gerund |  | snow |  |  |  | upon the delta | vn other\_cos-45.4-1 «NP V NP ADJ»: agent=Patient snow=Result |

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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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