---
title: Northern lights happen when charged bits from the Sun are guided by… — Compasses and the magnetic Earth · tree and pragmatics
description: Northern lights happen when charged bits from the Sun are guided by the Earth's magnetism down near the poles and make the high air glow; elsewhere the field shields us from them, and without it, over a very long time, they would strip away some of our air. Who acts: Northern lights, magnetism, fiel
---

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# Compasses and the magnetic Earth, sentence 11

<!-- .ven lang=en -->
Northern lights happen when charged bits from the Sun are guided by the Earth's magnetism down near the poles and make the high air glow; elsewhere the field shields us from them, and without it, over a very long time, they would strip away some of our air.

<!-- .vintro -->
**Who acts:** Northern lights, magnetism, field, lights · **What happens:** happen, charge, guide, make, shield, strip away · **To what, where:** charged bits, high air glow, us, some

<!-- .vabout -->
This is a sentence of the lesson «Compasses and the magnetic Earth» of the physics course of Mova's primary school. The page gives its syntax tree — a dependency tree in the style of Universal Dependencies — and its pragmatics clause by clause: who acts (Northern lights, magnetism, field, lights), what happens, when and where, as Mova's frames read it from the tree.

## The tree {#tree}

```conllu
# sent_id = school:physics:030-compasses-and-the-magnetic-earth.lesson:11
# text = Northern lights happen when charged bits from the Sun are guided by the Earth's magnetism down near the poles and make the high air glow; elsewhere the field shields us from them, and without it, over a very long time, they would strip away some of our air.
# source = school lesson (ours)
# course = physics
# lesson = 030-compasses-and-the-magnetic-earth.lesson
# annotation = Mova annot: Rust (en) → Haiku 5.5 (medium, Batches API) patches; gates UD 2.18; agreed by treeagree rules (Stanza, Trankit, spaCy trf): R5-strong ×1, R7-rel-agree ×1
1	Northern	northern	ADJ	JJ	Degree=Pos	2	amod	_	_
2	lights	light	NOUN	NNS	Number=Plur	3	nsubj	_	_
3	happen	happen	VERB	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	0	root	_	_
4	when	when	SCONJ	WRB	_	11	mark	_	_
5	charged	charge	VERB	VBN	Tense=Past|VerbForm=Part|Voice=Pass	6	amod	_	_
6	bits	bit	NOUN	NNS	Number=Plur	11	nsubj	_	_
7	from	from	ADP	IN	_	9	case	_	_
8	the	the	DET	DT	Definite=Def|PronType=Art	9	det	_	_
9	Sun	Sun	PROPN	NNP	Number=Sing	6	nmod	_	_
10	are	be	AUX	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	11	aux:pass	_	_
11	guided	guide	VERB	VBN	Tense=Past|VerbForm=Part|Voice=Pass	3	advcl	_	_
12	by	by	ADP	IN	_	16	case	_	_
13	the	the	DET	DT	Definite=Def|PronType=Art	14	det	_	_
14	Earth	Earth	PROPN	NNP	Number=Sing	16	nmod:poss	_	_
15	's	's	PART	POS	_	14	case	_	_
16	magnetism	magnetism	NOUN	NN	Number=Sing	11	obl	_	_
17	down	down	ADV	RB	_	11	advmod	_	_
18	near	near	ADP	IN	_	20	case	_	_
19	the	the	DET	DT	Definite=Def|PronType=Art	20	det	_	_
20	poles	pole	NOUN	NNS	Number=Plur	17	obl	_	_
21	and	and	CCONJ	CC	_	22	cc	_	_
22	make	make	VERB	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	11	conj	_	Agree=R5-strong|Haiku=3:conj|HaikuPos=VERB:VB:VerbForm=Inf
23	the	the	DET	DT	Definite=Def|PronType=Art	26	det	_	_
24	high	high	ADJ	JJ	Degree=Pos	26	amod	_	_
25	air	air	NOUN	NN	Number=Sing	26	compound	_	_
26	glow	glow	NOUN	NN	Number=Sing	22	obj	_	_
27	;	;	PUNCT	,	_	31	punct	_	_
28	elsewhere	elsewhere	ADV	RB	_	31	advmod	_	_
29	the	the	DET	DT	Definite=Def|PronType=Art	30	det	_	_
30	field	field	NOUN	NN	Number=Sing	31	nsubj	_	_
31	shields	shield	VERB	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	22	advcl	_	_
32	us	we	PRON	PRP	Case=Acc|Number=Plur|Person=1|PronType=Prs	31	obj	_	_
33	from	from	ADP	IN	_	34	case	_	_
34	them	they	PRON	PRP	Case=Acc|Number=Plur|Person=3|PronType=Prs	31	obl	_	_
35	,	,	PUNCT	,	_	48	punct	_	_
36	and	and	CCONJ	CC	_	48	cc	_	_
37	without	without	ADP	IN	_	38	case	_	_
38	it	it	PRON	PRP	Case=Nom|Gender=Neut|Number=Sing|Person=3|PronType=Prs	48	obl	_	_
39	,	,	PUNCT	,	_	38	punct	_	_
40	over	over	ADP	IN	_	44	case	_	_
41	a	a	DET	DT	Definite=Ind|PronType=Art	44	det	_	_
42	very	very	ADV	RB	_	43	advmod	_	_
43	long	long	ADJ	JJ	Degree=Pos	44	amod	_	_
44	time	time	NOUN	NN	Number=Sing	48	obl	_	_
45	,	,	PUNCT	,	_	44	punct	_	_
46	they	they	PRON	PRP	Case=Nom|Number=Plur|Person=3|PronType=Prs	48	nsubj	_	_
47	would	would	AUX	MD	VerbForm=Fin	48	aux	_	_
48	strip	strip	VERB	VB	VerbForm=Inf	3	conj	_	_
49	away	away	ADV	RB	_	48	compound:prt	_	Agree=R7-rel-agree|Haiku=48:advmod
50	some	some	DET	DT	PronType=Ind	48	obj	_	_
51	of	of	ADP	IN	_	53	case	_	_
52	our	our	PRON	PRP$	Case=Gen|Number=Plur|Person=1|Poss=Yes|PronType=Prs	53	nmod:poss	_	_
53	air	air	NOUN	NN	Number=Sing	50	nmod	_	_
54	.	.	PUNCT	.	_	3	punct	_	_
```

## Pragmatics {#pragmatics}

<!-- sa -->
- form: statement
- act: assert
- voice: narrator
- polarity: none
- teacher: changed act=assert

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **happen** | present | Northern lights |  |  |  |  |  | vn occur-48.3-1 «NP V»: agent=Theme |
| 2 | **charge** | participle |  |  |  |  |  |  | vn run-51.3.2 «NP V»: agent=Theme |
| 3 | **guide** | present · passive | the Earth's magnetism | charged bits from the Sun |  |  |  | down *property* | vn accompany-51.7 «NP V NP»: agent=Agent subject=Theme |
| 4 | **make** | present | the Earth's magnetism *not said here* | the high air glow |  |  |  |  | vn build-26.1-1 «NP.asset V NP»: agent=Asset glow=Product |
| 5 | **shield** | present | the field | us |  |  |  | from bits *= bit*; elsewhere *property* | tree rules |
| 6 | **strip away** | would | lights *= light* | some |  |  | time | without Pole | vn dress-41.1.1-1-1 «NP V NP»: agent=Agent some=Patient |

<!-- .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.

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**Licence: [CC BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/)**, as the whole of Mova corpus 0.4, of which this treebank (the agreed school, `mova-school-agreed-en.conllu`) is part. The lessons were written for Mova's primary school. Sentence `school:physics:030-compasses-and-the-magnetic-earth.lesson:11`.

**The tree:** Mova annot: Rust (en) → Haiku 5.5 (medium, Batches API) patches; gates UD 2.18; agreed by treeagree rules (Stanza, Trankit, spaCy trf): R5-strong ×1, R7-rel-agree ×1. **The frames** are read from the tree by Mova's frames reader (`prag`) when this page is built, the lesson read in order, so a pronoun may be resolved from an earlier sentence.

See the [release 0.4](https://md.mova.elamur.ai/free/en/releases/0.4/).

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