Plate tectonics

Tests: 4 of 10 right · Exam: 2 of 4 right · Kind: ★ · Understood: 6 of 14 · Run: 2026-10-18, commit f3c23ea72

Lesson 42 of the geography 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 ✗

Leo says the plates float on a sea of liquid lava. Put him right.

1. They float on the liquid inner core, which is made of hot iron — ← Mova's choice · no support
2. They ride on solid mantle rock that flows very slowly — ✓ the right answer · no support
3. He's right, the mantle is runny lava — no support
4. They sit on a layer of seawater — 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 2 · ★ · right ✓

"my nails grow like 3 cm a year, so plates are basically the same speed??" Is that roughly right?

1. No, plates don't move at all, they're stuck — score 0
2. No, plates move about 3 km a year, mate — score 4
3. No, plates move faster than a car on a road — score 3
4. Yes, plates move about 2-10 cm a year — ← Mova's choice · ✓ the right answer · score 12

Why: It took the question to ask which statement is true. It chose option 4 with score 12, against 4 for the next best. Its support: lesson 42, line 7: «Plates move about 2-10 cm a year, roughly as fast as your fingernails grow.», reached through the remembered sentence the question matched. What matched: the same thing acted on «2-10 cm» (+6); the same action «move about» (+3); the same property (+2); the same doer «plates» (+1). · the question and its options parsed, with trees and pragmatics

Test 3 · ★ · right ✓

What would happen if no plate ever sank into the mantle any more?

1. The main force pushing plates, slab pull, would stop — ← Mova's choice · ✓ the right answer · score 4
2. Plates would move much faster — score 4
3. New mountains would grow everywhere, on every continent, very fast — no support
4. The Earth would grow bigger each year — no support

Why: It took the question to ask what happens next. It chose option 1 with score 4, tied with another option at 4 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 42, line 8: «The biggest force moving plates is slab pull: old, cold ocean plate is heavy and sinks into the mantle, dragging the rest behind it.», reached through the same lesson line as the sentence the question matched. What matched: the same doer «biggest force» (+2); the same thing acted on «slab pull» (+2). · the question and its options parsed, with trees and pragmatics

Test 4 · ★ · right ✓

The Himalayas still grow a few millimetres a year. Which kind of plate edge explains this?

1. Two plates pulling apart and making new sea floor — score 4
2. An ocean plate sinking under a continent — score 4
3. Two continents colliding and crumpling the crust upwards — ← Mova's choice · ✓ the right answer · score 5
4. Two plates sliding past sideways — score 4

Why: It took the question to ask who or what does it. It chose option 3 with score 5, against 4 for the next best. Its support: lesson 42, line 14: «Alfred Wegener proposed in 1912 that continents drift, but most scientists rejected the idea until the 1960s, partly because he could not explain what moved th…», reached through the same lesson line as the sentence the question matched. What matched: it fills the role the question asks for (+4); the same doer «continents» (+3). Against it: a different action (counts against) (-2). · the question and its options parsed, with trees and pragmatics

Test 5 · ★ · right ✓

Japan has deep trenches offshore and a line of volcanoes. What is happening under it?

1. The plates are pulling apart there — score 5
2. An ocean plate is diving down in a subduction zone — ← Mova's choice · ✓ the right answer · score 6
3. Nothing, Japan sits safely in the middle of a big plate — no support
4. Two continents are colliding there — no support

Why: It took the question to ask which statement is true. It chose option 2 with score 6, against 5 for the next best. Its support: lesson 42, line 10: «Where an ocean plate meets another plate, the denser one dives down in a subduction zone, making a deep trench and a line of volcanoes.», reached through the same lesson line as the sentence the question matched. What matched: the same action «dive down» (+3); the same property (+2); the same circumstance (+2). Against it: a different doer (counts against) (-1). · the question and its options parsed, with trees and pragmatics

Test 6 · ★ · wrong ✗

"san andreas fault, mate, does it make volcanoes or what?"

1. No, nothing at all happens there — no support
2. Yes, it is the biggest volcano belt in the world, bigger than the whole of Japan — no support
3. Yes, magma rises where the plates pull apart — ← Mova's choice · score 5
4. No, plates slide sideways there, so it gives earthquakes, not volcanoes — ✓ the right answer · no support

Why: It took the question to ask which statement is true. It chose option 3 with score 5, the only option with support. Its support: lesson 42, line 4: «What happens at a plate's edge depends on how the plates meet: pulling apart makes new sea floor, one diving under another makes trenches and volcanoes, two co…», reached through the same lesson line as the sentence the question matched. What matched: the same action «pull apart» (+3); the same property (+2). The right option, 4, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 7 · ★ · wrong ✗

In a film, a crack opens and California floats off into the Pacific overnight. What's wrong?

1. Plates move only in winter — ← Mova's choice · no support
2. Nothing, that really happens every century or so, after the big earthquakes — no support
3. California is not on any plate — no support
4. Plates slide past each other a few cm a year, not open in a night — ✓ 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 8 · ★ · wrong ✗

Iceland sits right on the Mid-Atlantic Ridge. What would you expect there?

1. No earthquakes or volcanoes at all — ← Mova's choice · no support
2. Huge mountains made by colliding continents — no support
3. Volcanoes and the land slowly being pulled apart — ✓ the right answer · no support
4. A deep ocean trench — 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 9 · ★ · wrong ✗

Why did Wegener's idea win in the end?

1. Wegener found a map from Roman times that showed the continents joined — ← Mova's choice · no support
2. Magnetic stripes on the sea floor showed new crust spreading from the ridges — ✓ the right answer · no support
3. Astronauts saw the continents moving — no support
4. The idea was voted for by schoolchildren — 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 10 · ★ · wrong ✗

Your mate says the Atlantic is shrinking, so New York is getting closer to London. Right?

1. Yes, about a metre closer each year — ← Mova's choice · no support
2. Yes, about 2.5 cm closer each year — no support
3. No, GPS shows them moving apart about 2.5 cm a year — ✓ the right answer · no support
4. No, the distance has never changed at all, not by a single centimetre — 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

Exam question 1 · formal language · right ✓

Identify the principal force to which the motion of the lithospheric plates is attributed.

1. The descent of cold, dense oceanic lithosphere into the mantle, termed slab pull — ← Mova's choice · ✓ the right answer · no support
2. The flow of rivers across the margins of the continents — no support
3. The gravitational attraction exerted upon the continents by the Moon and the Sun together — no support
4. The pressure of prevailing winds upon the continental surfaces — 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

Exam question 2 · formal language · wrong ✗

Which of the following statements most accurately characterises a divergent plate boundary such as the Mid-Atlantic Ridge?

1. Two continental masses collide and form mountains — ← Mova's choice · no support
2. One plate descends beneath another into a trench — no support
3. Plates separate and ascending magma forms new crust — ✓ the right answer · no support
4. Plates move laterally and crust is neither formed nor destroyed — 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

Exam question 3 · formal language · wrong ✗

It is given that two continental plates converge. Ascertain the consequence that is consistent with the established facts.

1. The lighter plate descends into the mantle forming a trench — ← Mova's choice · score 7
2. A mid-ocean ridge is formed between the two plates — score 6
3. Both plates melt entirely and are replaced by oceanic crust — no support
4. Neither plate is subducted and the crust is uplifted into a mountain range — ✓ the right answer · no support

Why: It took the question to ask which statement is true. It chose option 1 with score 7, against 6 for the next best. Its support: lesson 42, line 4: «What happens at a plate's edge depends on how the plates meet: pulling apart makes new sea floor, one diving under another makes trenches and volcanoes, two co…», reached through the same lesson line as the sentence the question matched. What matched: the same action «make» (+3); the same doer «plates» (+3); a different thing acted on (counts against) (+1). The right option, 4, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Exam question 4 · formal language · right ✓

Select the response that is consistent with the established facts concerning the reception of Wegener's hypothesis of continental drift.

1. It was proposed in 1912 and largely rejected until the evidence of the 1960s — ← Mova's choice · ✓ the right answer · no support
2. It was proposed in the 1960s and accepted immediately by every geologist — no support
3. It was universally accepted upon its publication in 1912 — no support
4. It was refuted conclusively and has since been abandoned — 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/geography/42-plate-tectonics/