How stars live

Tests: 4 of 11 right · Exam: 2 of 4 right · Kind: ★★ · Understood: 8 of 15 · Run: 2026-10-18, commit f3c23ea72

Lesson 18 of the space course of Mova's primary school, as Mova's small model took its tests: it had read this lesson and the ones before it and learned from their exercises. Each test shows the options in the order the student saw them, its choice, the right answer, the score of every option and why it chose. The lesson itself, sentence by sentence with trees and pragmatics: the lesson in the corpora.

Every question of this lesson and each of its options parsed by Mova, with trees and pragmatics: the lesson's questions in the corpora.

Test 1 · ★★ · wrong ✗

My cousin reckons bigger stars must live longer cos they've got more fuel. what's wrong with that?

1. Stars do not use any fuel at all — score 5
2. Nothing, the biggest stars live longest because they have more fuel — ← Mova's choice · score 7
3. Big stars burn their fuel so fast they die much sooner — ✓ the right answer · score 7
4. Big stars have less fuel than small ones — score 7

Why: It took the question to ask which statement is true. It chose option 2 with score 7, tied with another option at 7 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 18, line 4: «Big stars live fast and die young, like a huge bonfire that burns out quickly, while tiny red dwarfs sip their fuel so slowly they can last trillions of years.», reached through the remembered sentence the question matched. What matched: the same doer «tiny red dwarfs» (+4); the same thing acted on «fuel» (+3). The right option, 3, scored 7. · the question and its options parsed, with trees and pragmatics

Test 2 · ★★ · wrong ✗

If gravity in a star suddenly got much weaker than the push of its hot gas, what would happen?

1. The star would turn into a planet — ← Mova's choice · no support
2. The star would swell outwards — ✓ the right answer · no support
3. The star would shrink to a point — no support
4. Nothing would change — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 3 · ★★ · right ✓

A telescope photo shows dark dusty columns with glowing spots inside. What is probably going on?

1. New stars are forming in a nebula — ← Mova's choice · ✓ the right answer · score 6
2. A black hole is swallowing a galaxy — no support
3. A star is being eaten by a planet — score 3
4. Comets are crashing together — no support

Why: It took the question to ask where. It chose option 1 with score 6, against 3 for the next best. Its support: lesson 18, line 8: «The Pillars of Creation in the Eagle Nebula are towering columns of gas and dust, each several light years tall, where new stars are forming.», reached through the same lesson line as the sentence the question matched. What matched: the same action «form» (+3); the same doer «new stars» (+3). · the question and its options parsed, with trees and pragmatics

Test 4 · ★★ · right ✓

Ollie says the Sun's nearly dead, we're doomed lol. is he right

1. Yes, it will die next year — score 6
2. Yes, it is almost out of fuel — no support
3. No, it is only about halfway through its life of about 10 billion years — ← Mova's choice · ✓ the right answer · score 10
4. No, the Sun will live for ever — score 7

Why: It took the question to ask which statement is true. It chose option 3 with score 10, against 7 for the next best. Its support: lesson 18, line 3: «Stars spend about 90% of their lives steadily turning hydrogen into helium; the Sun is about 4.6 billion years old, roughly halfway through its life of about 1…», reached through the remembered sentence the question matched. What matched: the same doer «sun» (+4); the same place «life» (+3); the same light verb (be, have, do, get, go) (+2); the same property (+1). · the question and its options parsed, with trees and pragmatics

Test 5 · ★★ · wrong ✗

A teacher says "we are made of star stuff". What does that mean?

1. We glow in the dark like stars — ← Mova's choice · no support
2. People came to the Earth from other stars — no support
3. People first came to the Earth from planets around other stars long ago — no support
4. Much of the carbon and oxygen in us was made inside earlier stars — ✓ the right answer · no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 6 · ★★ · wrong ✗

Which star would you bet on to still be shining in a trillion years?

1. A star 10 times heavier than the Sun — score 5
2. A big blue-white star — ← Mova's choice · score 6
3. A small red dwarf — ✓ the right answer · score 6
4. The Sun — no support

Why: It took the question to ask who or what does it. It chose option 2 with score 6, tied with another option at 6 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 17, line 10: «Star colours show their temperature: red stars are coolest at about 3,000 °C, the Sun is yellow-white at about 5,500 °C, and blue-white stars can be over 20,00…», reached through the option's own match among the sentences about the question's things. What matched: it fills the role the question asks for (+3); the same doer «white stars» (+2); the same property (+1). The right option, 3, scored 6. · the question and its options parsed, with trees and pragmatics

Test 7 · ★★ · right ✓

Why are the stars of the Pleiades close together in the sky?

1. They are the bright leftovers of a big comet that broke up near the Sun — no support
2. They were born from the same cloud and stay together for a while — ← Mova's choice · ✓ the right answer · score 7
3. They were pushed together into one small group by the pull of Jupiter — no support
4. They are all the same star seen many times over because its light bends — score 5

Why: It took the question to ask why something happens (its cause). It chose option 2 with score 7, against 5 for the next best. Its support: lesson 18, line 16: «Stars born from the same cloud often stay together for a while as a cluster, like the Pleiades, about 440 light years away and about 100 million years old.», reached through the same lesson line as the sentence the question matched. What matched: the same thing acted on «stars» (+3); the same action «bear» (+2); the same place «same cloud» (+2). · the question and its options parsed, with trees and pragmatics

Test 8 · ★★ · wrong ✗

In a game, a star forms in a bright, empty, hot patch of space. what's wrong with that

1. Stars form inside planets — ← Mova's choice · score 7
2. Nothing, stars need empty space — no support
3. Stars form in cold clouds of gas and dust — ✓ the right answer · score 7
4. Stars only form near the Earth — score 7

Why: It took the question to ask which statement is true. It chose option 1 with score 7, tied with another option at 7 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 18, line 8: «The Pillars of Creation in the Eagle Nebula are towering columns of gas and dust, each several light years tall, where new stars are forming.», reached through the remembered sentence the question matched. What matched: the same doer «new stars» (+4); the same action «form» (+3). The right option, 3, scored 7. · the question and its options parsed, with trees and pragmatics

Test 9 · ★★ · wrong ✗

If the Sun gets about 10% brighter every billion years, how will the Earth change over that time?

1. It will not change at all — no support
2. It will slowly freeze over — ← Mova's choice · score 7
3. It will slowly get warmer — ✓ the right answer · no support
4. It will move closer to Mars — no support

Why: It took the question to ask what something is like. It chose option 2 with score 7, the only option with support. Its support: lesson 5, line 3: «The Earth leans over by about 23.4 degrees, and this tilt, not our distance from the Sun, makes summer and winter: in summer your half leans towards the Sun.», reached through the option's own match among the sentences about the question's things. What matched: the same doer «earth» (+4); it fills the role the question asks for (+3); the same property (+1). Against it: a different action (counts against) (-1). The right option, 3, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 10 · ★★ · wrong ✗

Which is true?

1. The Sun and the universe are the same age — ← Mova's choice · no support
2. The universe is about 13.8 billion years old and the Sun about 4.6 billion — ✓ the right answer · no support
3. The universe is only 4.6 billion years old, and the Sun is just as old as it — no support
4. The Sun is older than the universe — no support

Why: Nothing it remembers matched the question, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 11 · ★★ · right ✓

why is a protostar hidden lol, is it shy

1. It is inside a planet — no support
2. It is wrapped in the dust of the cloud it formed from — ← Mova's choice · ✓ the right answer · score 4
3. It is behind the Sun — no support
4. It gives no light at all — no support

Why: It took the question to ask which statement is true. It chose option 2 with score 4, the only option with support. Its support: lesson 18, line 1: «Stars are born inside huge, cold clouds of gas and dust called nebulae: a clump collapses under its own gravity, heats up and glows as a protostar hidden in du…», reached through the remembered sentence the question matched. What matched: the same thing acted on «protostar» (+3); the same place «dust» (+3). Against it: a different action (counts against) (-2). · the question and its options parsed, with trees and pragmatics

Exam question 1 · formal language · wrong ✗

Identify the principal factor which determines the lifespan of a star.

1. Its colour alone — ← Mova's choice · no support
2. The number of its planets — no support
3. Its distance from the Earth — no support
4. Its mass — ✓ the right answer · no support

Why: Nothing it remembers matched the question, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Exam question 2 · formal language · wrong ✗

Select the response that is consistent with the established facts concerning the equilibrium of a star upon the main sequence.

1. Magnetism is balanced by the pressure of light — ← Mova's choice · no support
2. No forces act upon it whatsoever — no support
3. The pull of the Earth is balanced by that of the Moon — no support
4. Inward gravitation is balanced by the outward pressure of hot gas — ✓ the right answer · no support

Why: Nothing it remembers matched the question, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Exam question 3 · formal language · right ✓

State the approximate age of the Sun as presently established.

1. Four point six billion years — ← Mova's choice · ✓ the right answer · no support
2. One hundred million years — no support
3. Thirteen point eight billion years — no support
4. Six thousand years — no support

Why: Nothing it remembers matched the question, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Exam question 4 · formal language · right ✓

Ascertain the locations within which the formation of stars takes place.

1. Cold clouds of gas and dust designated nebulae — ← Mova's choice · ✓ the right answer · no support
2. The interiors of planets, beneath their rocky surfaces — no support
3. The surfaces of comets — no support
4. The cores of existing stars — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

This page in Markdown → https://md.mova.elamur.ai/free/en/school-run/space/18-how-stars-live/