Diggers, cranes and cement mixers
Tests: 7 of 11 right · Exam: 2 of 4 right · Kind: ★ · Understood: 11 of 15 · Run: 2026-10-18, commit f3c23ea72
Lesson 28 of the technology 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 ✗
«the site's empty on Sunday, let's go play on the sand piles» What is right?
- 1. Fine, there are no machines on Sundays, so there's nothing that can hurt you — ← Mova's choice · no support
- 2. Never go in: building sites are dangerous even when empty — ✓ the right answer · no support
- 3. Fine, if one of you keeps watch — no support
- 4. Fine, if you stay on the sand — 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 · ★ · wrong ✗
«concrete's just mud that dries, innit» What is right?
- 1. No, it sets because it freezes — no support
- 2. Yes, so rain makes it go soft and runny again later — no support
- 3. No, it sets by a chemical reaction with water — ✓ the right answer · score 3
- 4. Yes, it dries in the sun like mud — ← Mova's choice · score 6
Why: It took the question to ask which statement is true. It chose option 4 with score 6, against 3 for the next best. Its support: lesson 2, line 8: «Farmers cut the pods, scoop out the beans, let them ferment (slowly change and turn a little sour, helped by tiny living things) under leaves for several days…», reached through the remembered sentence the question matched. What matched: the same action «dry» (+4); the same place «sun» (+4). Against it: a different doer (counts against) (-2). The right option, 3, scored 3. · the question and its options parsed, with trees and pragmatics
Test 3 · ★ · right ✓
In a cartoon, a crane lifts a whole house and does not tip, with nothing on its short arm. What is wrong?
- 1. Without counterweights on the short arm, the crane would tip over — ← Mova's choice · ✓ the right answer · score 2
- 2. Nothing, cranes are always strong enough — no support
- 3. The house would make the crane taller — no support
- 4. Cranes never lift anything heavy — score 2
Why: It took the question to ask which statement is true. It chose option 1 with score 2, tied with another option at 2 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 28, line 9: «A mobile crane is a crane on a lorry with an arm that slides out like a telescope; it puts out legs before lifting so it does not tip over.», reached through a sentence linked to the one the question matched. What matched: the same action «tip over» (+2); the same doer «crane» (+2); the same property (+1). Against it: one says «not», the other does not (counts against) (-3). · the question and its options parsed, with trees and pragmatics
Test 4 · ★ · wrong ✗
What would happen if a mixer lorry got stuck in traffic and its drum stopped turning for hours?
- 1. Nothing, concrete never sets while it is inside a lorry — no support
- 2. The drum would start turning on its own — ← Mova's choice · score 8
- 3. The concrete could set hard inside the drum — ✓ the right answer · score 1
- 4. The concrete would turn back into sand — no support
Why: It took the question to ask which statement is true. It chose option 2 with score 8, against 1 for the next best. Its support: lesson 28, line 10: «A cement mixer lorry keeps its drum turning so the concrete does not set; spiral fins inside mix it one way and push it out the other way.», reached through the remembered sentence the question matched. What matched: the same action «turn» (+4); the same doer «drum» (+4). The right option, 3, scored 1. · the question and its options parsed, with trees and pragmatics
Test 5 · ★ · right ✓
«the crane's swinging a load over us, cool, let's stand right under it» What is right?
- 1. Never stand under a load: it could fall — ← Mova's choice · ✓ the right answer · score 2
- 2. Only dangerous at night — no support
- 3. It's fine, if you wear a cap — no support
- 4. It's safe, cranes never drop anything, the hooks lock shut — no support
Why: It took the question to ask which statement is true. It chose option 1 with score 2, the only option with support. Its support: lesson 1, line 16: «A forklift truck lifts pallets on two steel forks, and a heavy counterweight at the back, which can weigh as much as a small car, stops it tipping forward; for…», reached through the option's own match among the sentences about the question's things. What matched: the same action «stand» (+2). · the question and its options parsed, with trees and pragmatics
Test 6 · ★ · right ✓
«why's the digger on tracks, wheels'd be faster, they're thick» What is the smart answer?
- 1. Wheels would break the digger — no support
- 2. Tracks make the digger lighter — no support
- 3. Tracks spread the weight so the digger does not sink in mud — ← Mova's choice · ✓ the right answer · score 2
- 4. Tracks are only for show — no support
Why: It took the question to ask why something happens (its cause). It chose option 3 with score 2, the only option with support. Its support: lesson 28, line 5: «A digger's engine drives a pump that pushes oil into pistons, called hydraulics, which move the arm and bucket with huge force; its tracks spread its weight so…», reached through the option's own match among the sentences about the question's things. What matched: the same thing acted on «weight» (+2). · the question and its options parsed, with trees and pragmatics
Test 7 · ★ · right ✓
It is very windy and the tower crane stands still all day. Why?
- 1. Cranes stop in high winds to stay safe — ← Mova's choice · ✓ the right answer · score 7
- 2. Cranes only work in the rain when it's cooler — score 5
- 3. The crane's battery ran out in the night — no support
- 4. The driver could not find the ladder up — score 3
Why: It took the question to ask why something happens (its cause). It chose option 1 with score 7, against 5 for the next best. Its support: lesson 28, line 8: «A tower crane driver usually climbs a long ladder inside the mast and works high up in the cab for hours; cranes stop in high winds, and nobody stands under a…», reached through the same lesson line as the sentence the question matched. What matched: the same action «stop» (+3); the same doer «cranes» (+2); the same place «high winds» (+2). · the question and its options parsed, with trees and pragmatics
Test 8 · ★ · right ✓
Why do tall buildings need piles under them?
- 1. To stop worms getting in — score 4
- 2. To carry their weight down to firm ground — ← Mova's choice · ✓ the right answer · score 9
- 3. To keep water out of the basement — score 4
- 4. To give the tower crane something firm to stand on while it works — score 4
Why: It took the question to ask why something happens (its cause). It chose option 2 with score 9, against 4 for the next best. Its support: lesson 28, line 15: «A pile driver drives long posts, called piles, deep into the ground to hold up buildings by carrying their weight down to firm ground, and tall buildings can s…», reached through the same lesson line as the sentence the question matched. What matched: the same action «carry down» (+3); the same thing acted on «weight» (+2); the same place «firm ground» (+2); the same property (+2). · the question and its options parsed, with trees and pragmatics
Test 9 · ★ · right ✓
«a monster truck at the mine had tyres taller than my dad» Could that be true?
- 1. No, no tyre is taller than a bike wheel — no support
- 2. No, mine trucks have no tyres, only tracks — score 10
- 3. Only in films — no support
- 4. Yes, the biggest mining dump trucks have tyres taller than an adult — ← 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 10 for the next best. Its support: lesson 28, line 13: «A dumper truck has a big bin that tips up to empty; the largest mining dump trucks carry hundreds of tonnes and have tyres taller than an adult.», reached through the remembered sentence the question matched. What matched: the same doer «largest dump trucks» (+4); the same thing acted on «tyres» (+4); the same property (+2); the same light verb (be, have, do, get, go) (+2). · the question and its options parsed, with trees and pragmatics
Test 10 · ★ · right ✓
«how do they fix the street lights, climb the pole?» What do they usually use?
- 1. They use a tall kitchen ladder — score 4
- 2. A cherry picker that lifts them on a platform — ← Mova's choice · ✓ the right answer · score 6
- 3. They take the whole lamppost down each time and put it back up after — score 3
- 4. They throw a rope over the top — no support
Why: It took the question to ask what something is like. It chose option 2 with score 6, against 4 for the next best. Its support: lesson 28, line 16: «A cherry picker lifts workers on a platform at the end of a folding hydraulic arm, and they wear harnesses clipped to the platform; fire brigades use similar m…», reached through the same lesson line as the sentence the question matched. What matched: the same place «platform» (+3); the same action «lift» (+2); the same doer «cherry picker» (+2). Against it: a different thing acted on (counts against) (-1). · the question and its options parsed, with trees and pragmatics
Test 11 · ★ · wrong ✗
Count them: a mobile crane puts out 4 legs, and there are 3 cranes on the site. How many legs?
- 1. 7 — ← Mova's choice · no support
- 2. 4 — no support
- 3. 12 — ✓ the right answer · no support
- 4. 16 — 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 · wrong ✗
Identify the principle by which the arm of an excavator exerts considerable force upon a slight movement of the control lever.
- 1. The bucket is rendered buoyant by the admission of air — ← Mova's choice · no support
- 2. Hydraulics, whereby a pump forces oil, which is incompressible, into pistons — ✓ the right answer · no support
- 3. Magnets attract the soil into the bucket — no support
- 4. The arm is connected to the lever by a rope and pulley — 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 · right ✓
Select the response consistent with the established facts concerning the hardening of concrete.
- 1. Concrete hardens by means of a chemical reaction with water — ← Mova's choice · ✓ the right answer · score 6
- 2. Concrete hardens only when compressed by a roller — no support
- 3. Concrete hardens solely by evaporation of its water in the heat of the sun — no support
- 4. Concrete hardens exclusively by freezing — no support
Why: It took the question to ask which statement is true. It chose option 1 with score 6, the only option with support. Its support: lesson 28, line 11: «Concrete sets because of a chemical reaction with water, not because it dries; wet cement can burn skin.», reached through the remembered sentence the question matched. What matched: the same doer «concrete» (+4); the same circumstance (+4). Against it: a different action (counts against) (-2). · the question and its options parsed, with trees and pragmatics
Exam question 3 · formal language · wrong ✗
Ascertain the function of the concrete blocks mounted upon the short arm of a tower crane.
- 1. They furnish the crane driver with a place to rest — ← Mova's choice · no support
- 2. They render the crane more conspicuous to aircraft — no support
- 3. They counterbalance the load so that the crane does not overturn — ✓ the right answer · no support
- 4. They are spare materials awaiting use in the construction of the building — 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 4 · formal language · right ✓
Which of the following statements most accurately characterises the conduct required of a child in respect of a building site?
- 1. A child shall not enter a building site, even when it appears to be unattended — ← Mova's choice · ✓ the right answer · score 10
- 2. A child may enter a building site provided that the machines are stationary — score 7
- 3. A child may enter a building site if wearing a hard hat — score 7
- 4. A child may enter a building site on Sundays — score 7
Why: It took the question to ask who or what does it. It chose option 1 with score 10, against 7 for the next best. Its support: lesson 28, line 4: «All these machines are amazing to watch, and the only safe place to watch them from is behind the fence. Building sites are dangerous even when they look empty…», 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 (+4); the same action «go in» (+3); the same doer «children» (+3). · the question and its options parsed, with trees and pragmatics
This page in Markdown → https://md.mova.elamur.ai/free/en/school-run/technology/28-diggers-cranes-and-cement-mixers/