---
title: The Earth's sky is blue because air scatters blue sunlight in all di… — Thinking like an astronomer · tree and pragmatics
description: The Earth's sky is blue because air scatters blue sunlight in all directions. Who acts: sky, air. A sentence of the lesson «Thinking like an astronomer» of the world course of Mova's primary school with its dependency tree and the pragmatics of every clause.
---

<!-- md -->
[Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/world/10-reasoning-about-space/13/)

<!-- crumbs -->
[home](https://md.mova.elamur.ai/free/en/) / [corpora](https://md.mova.elamur.ai/free/en/corpora/) / [school](https://md.mova.elamur.ai/free/en/corpora/school/) / [World](https://md.mova.elamur.ai/free/en/corpora/school/world/) / [Thinking like an astronomer](https://md.mova.elamur.ai/free/en/corpora/school/world/10-reasoning-about-space/) / 13

# Thinking like an astronomer, sentence 13

<!-- .ven lang=en -->
The Earth's sky is blue because air scatters blue sunlight in all directions.

<!-- .vintro -->
**Who acts:** sky, air · **What happens:** be, scatter · **To what, where:** blue sunlight, directions

<!-- .vabout -->
This is a sentence of the lesson «Thinking like an astronomer» of the world 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 (sky, air), what happens, when and where, as Mova's frames read it from the tree.

## The tree {#tree}

```conllu
# sent_id = school:world:010-reasoning-about-space.lesson:13
# text = The Earth's sky is blue because air scatters blue sunlight in all directions.
# source = school lesson (ours)
# course = world
# lesson = 010-reasoning-about-space.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): no change
1	The	the	DET	DT	Definite=Def|PronType=Art	2	det	_	_
2	Earth	Earth	PROPN	NNP	Number=Sing	4	nmod:poss	_	_
3	's	's	PART	POS	_	2	case	_	_
4	sky	sky	NOUN	NN	Number=Sing	6	nsubj	_	_
5	is	be	AUX	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	6	cop	_	_
6	blue	blue	ADJ	JJ	Degree=Pos	0	root	_	_
7	because	because	SCONJ	IN	_	9	mark	_	_
8	air	air	NOUN	NN	Number=Sing	9	nsubj	_	_
9	scatters	scatter	VERB	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	6	advcl	_	_
10	blue	blue	ADJ	JJ	Degree=Pos	11	amod	_	_
11	sunlight	sunlight	NOUN	NN	Number=Sing	9	obj	_	_
12	in	in	ADP	IN	_	14	case	_	_
13	all	all	DET	DT	PronType=Tot	14	det	_	_
14	directions	direction	NOUN	NNS	Number=Plur	9	obl	_	_
15	.	.	PUNCT	.	_	6	punct	_	_
```

## Pragmatics {#pragmatics}

<!-- .note -->
No stored speech act for this sentence.

<!-- .fr -->
| # | verb | tense, mood | who | what, whom | to whom | where | when | other | roles by |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | **is** | present | the Earth's sky |  |  |  |  | blue *property* | tree rules |
| 2 | **scatter** | present | air | blue sunlight |  | all directions |  |  | vn spray-9.7-1 «NP V NP PP.destination»: agent=Agent sunlight=Theme in direction=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.

<!-- div src -->

**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:world:010-reasoning-about-space.lesson:13`.

**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): no change. **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/).

<!-- /div -->

<!-- pn -->
- ← previous: [Thinking like an astronomer, 12](https://md.mova.elamur.ai/free/en/corpora/school/world/10-reasoning-about-space/12/)
- next →: [Thinking like an astronomer, 14](https://md.mova.elamur.ai/free/en/corpora/school/world/10-reasoning-about-space/14/)
- ↑ back to [the lesson](https://md.mova.elamur.ai/free/en/corpora/school/world/10-reasoning-about-space/)