The fish tank: water, gills, heaters and the right neighbours
Tests: 5 of 12 right · Exam: 3 of 4 right · Kind: ★★ · Understood: 11 of 16 · Run: 2026-10-18, commit f3c23ea72
Lesson 203 of the biology 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 ✗
«got a tank for my bday, filled it up, chuck the fish in now yeah?» What is right?
- 1. Wait while helpful bacteria grow, or the fish may die — ✓ the right answer · score 6
- 2. Yes, and add extra food too — no support
- 3. No, never add fish at all — ← Mova's choice · score 9
- 4. Yes, put them all in at once while the water is fresh — no support
Why: It took the question to ask which statement is true. It chose option 3 with score 9, against 6 for the next best. Its support: lesson 92, line 1: «Some of the strangest animals in the aquarium are not fish at all: jellyfish, octopuses, cuttlefish, sea stars and lobsters have no backbone, which makes them…», reached through the option's own match among the sentences about the question's things. What matched: the same place «all» (+5); the same thing acted on «fish» (+4). The right option, 1, scored 6. · the question and its options parsed, with trees and pragmatics
Test 2 · ★★ · wrong ✗
«Nemo's dad lived in the sea, so I'll put a clownfish in my cold tap-water tank» What is right?
- 1. Any fish can live in any water — ← Mova's choice · score 7
- 2. Clownfish need warm sea water, so this would kill it — ✓ the right answer · no support
- 3. Clownfish love cold tap water — no support
- 4. Clownfish only live in films — score 3
Why: It took the question to ask which statement is true. It chose option 1 with score 7, against 3 for the next best. Its support: lesson 203, line 14: «Real clownfish like Nemo live in warm sea water among anemones (soft stinging sea animals that look like flowers), and after the Finding Nemo films many people…», reached through the option's own match among the sentences about the question's things. What matched: the same place «warm sea water» (+5); the same action «live» (+3). Against it: a different doer (counts against) (-1). The right option, 2, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics
Test 3 · ★★ · right ✓
«the fish never shuts its eyes, is it a zombie lol» What is the truth?
- 1. It is watching you all night because it does not trust you — no support
- 2. It never sleeps — no support
- 3. It is ill — no support
- 4. Fish have no eyelids, so they sleep with eyes open — ← Mova's choice · ✓ the right answer · score 14
Why: It took the question to ask what it is done to. It chose option 4 with score 14, the only option with support. Its support: lesson 203, line 9: «Fish have no eyelids, so they sleep with their eyes open, resting quietly near the bottom or among plants, and some parrotfish wrap themselves in a bubble of s…», reached through the option's own match among the sentences about the question's things. What matched: the same circumstance (+5); the same action «sleep» (+4); the same doer «fish» (+3); its «because» matches the remembered cause (+2). · the question and its options parsed, with trees and pragmatics
Test 4 · ★★ · wrong ✗
What would happen if you fed the fish a whole pot of food every day?
- 1. The fish would grow huge and healthy — ← Mova's choice · score 0
- 2. The water would get cleaner — no support
- 3. The fish would save it for winter — no support
- 4. The leftovers would rot and foul the water — ✓ the right answer · no support
Why: It took the question to ask what happens next. It chose option 1 with score 0, the only option with support. Its support: lesson 152, line 13: «Goldfish must never be let go in the wild, where they can grow huge and harm native fish.», reached through the option's own match among the sentences about the question's things. What matched: the same action «grow» (+1). Against it: the same doer «fish» (-1). The right option, 4, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics
Test 5 · ★★ · wrong ✗
«put the big oscar in with the tiny neons, they'll be mates» What is likely?
- 1. They will all be friends — ← Mova's choice · no support
- 2. The little ones will gang up together and eat the oscar — no support
- 3. The big fish may eat the little ones — ✓ the right answer · no support
- 4. They will swap colours — 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 ✗
«my betta's in a jam jar, he doesn't need more, right?» What is right?
- 1. He should share with another male betta — no support
- 2. A jam jar is perfect — no support
- 3. He needs a bigger warm tank with a filter — ✓ the right answer · no support
- 4. He needs ice water — ← Mova's choice · score 2
Why: It took the question to ask which statement is true. It chose option 4 with score 2, the only option with support. Its support: lesson 202, line 15: «Small pets need clean bedding, fresh water, the right food and things to do every day, and hamsters live only about two to three years.», reached through the remembered sentence the question matched. What matched: the same thing acted on «clean bedding» (+4); the same action «need» (+1). Against it: a different doer (counts against) (-3). The right option, 3, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics
Test 7 · ★★ · right ✓
In a cartoon two fish chat and breathe bubbles of air out of their mouths. How do real fish breathe?
- 1. They breathe through their tails — score 8
- 2. They breathe the little air bubbles they make with their mouths — score 8
- 3. They take oxygen out of the water through their gills — ← Mova's choice · ✓ the right answer · score 15
- 4. They hold their breath all day — score 7
Why: It took the question to ask what something is like. It chose option 3 with score 15, against 8 for the next best. Its support: lesson 203, line 6: «Fish take oxygen from water through their gills, and a filter, moving water and air bubbles help mix more oxygen into the water.», reached through the option's own match among the sentences about the question's things. What matched: the same action «take» (+5); the same thing acted on «oxygen» (+3); the same place «water» (+3); the same doer «fish» (+2). · the question and its options parsed, with trees and pragmatics
Test 8 · ★★ · right ✓
«that ugly sucker fish is licking the glass, gross» What is it doing?
- 1. Licking the glass for salt — no support
- 2. Talking to the cat outside the glass — no support
- 3. Trying to get out of the tank — no support
- 4. Cleaning off algae to eat — ← Mova's choice · ✓ the right answer · score 4
Why: It took the question to ask what is done. It chose option 4 with score 4, the only option with support. Its support: lesson 203, line 10: «Fish that are small enough to fit in another fish's mouth may be eaten, so owners check how big each fish will grow before putting them together.», reached through the same lesson line as the sentence the question matched. What matched: it fills the role the question asks for (+3); the same action «eat» (+2). Against it: a different thing acted on (counts against) (-1). · the question and its options parsed, with trees and pragmatics
Test 9 · ★★ · right ✓
Count them: a tank has 5 neon tetras and 2 angelfish. How many eyes?
- 1. 14 — ← Mova's choice · ✓ the right answer · no support
- 2. 7 — no support
- 3. 10 — no support
- 4. 28 — 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 ✗
Count them: 3 fish and a pet crab with ten legs in the tank. How many legs?
- 1. 22 — ← Mova's choice · no support
- 2. 10 — ✓ the right answer · no support
- 3. 12 — no support
- 4. 8 — 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 11 · ★★ · wrong ✗
«I tapped the glass and they all shot behind the plants» Why?
- 1. Fish feel the movement and hide from danger — ✓ the right answer · no support
- 2. They were going to sleep — no support
- 3. They are deaf so they hid — no support
- 4. They wanted the plants to eat — ← Mova's choice · score 6
Why: It took the question to ask why something happens (its cause). It chose option 4 with score 6, the only option with support. Its support: lesson 171, line 12: «Tiny drifting plants called phytoplankton bloom in the Southern Ocean in spring, and whale poo helps feed them because it contains iron they need.», reached through the option's own match among the sentences about the question's things. What matched: the same doer «plants» (+3); the same action «need» (+2); a different thing acted on (counts against) (+1). The right option, 1, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics
Test 12 · ★★ · right ✓
«why do they bother with real plants, plastic ones are easier» What do living plants add?
- 1. They eat the fish — score 6
- 2. They use up some waste, add oxygen and give hiding places — ← Mova's choice · ✓ the right answer · score 8
- 3. Nothing at all — no support
- 4. They make the water salty, just like the sea that fish come from — score 6
Why: It took the question to ask why something happens (its cause). It chose option 2 with score 8, against 6 for the next best. Its support: lesson 203, line 15: «Living plants use up some fish waste, add oxygen in the light and give fish places to hide.», reached through the option's own match among the sentences about the question's things. What matched: the same doer «living plants» (+3); the same thing acted on «fish waste» (+3); the same action «use up» (+2). · the question and its options parsed, with trees and pragmatics
Exam question 1 · formal language · right ✓
Which of the following statements most accurately characterises the necessity of cycling a newly established aquarium?
- 1. Time is required for beneficial bacteria to develop which break down the waste of the fish — ← Mova's choice · ✓ the right answer · no support
- 2. The fish must be trained to swim in circles — no support
- 3. The glass must be allowed to harden — no support
- 4. The water must be boiled before the fish are introduced, so that no living thing remains in it — 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 ✓
Identify the means by which fish obtain oxygen.
- 1. Through the gills, from oxygen dissolved in the water — ← Mova's choice · ✓ the right answer · score 12
- 2. Through lungs, from air at the surface in all species — no support
- 3. Fish possess no requirement for oxygen — score 2
- 4. Through the fins, from the light — no support
Why: It took the question to ask which statement is true. It chose option 1 with score 12, against 2 for the next best. Its support: lesson 203, line 2: «Fish breathe the oxygen dissolved in water through their gills, and their droppings make waste that would poison them if friendly bacteria in the filter did no…», reached through the option's own match among the sentences about the question's things. What matched: the same place «water» (+5); the same thing acted on «oxygen» (+4); the same action «dissolve» (+3). · the question and its options parsed, with trees and pragmatics
Exam question 3 · formal language · right ✓
It is given that a large fish and several small fish are proposed to share a single aquarium. Ascertain the principal consideration.
- 1. Fish of differing colours are invariably hostile — no support
- 2. Small fish invariably consume large fish — score 4
- 3. Any fish small enough to fit within the mouth of another may be consumed — ← Mova's choice · ✓ the right answer · score 5
- 4. No consideration is required whatsoever — no support
Why: It took the question to ask which statement is true. It chose option 3 with score 5, against 4 for the next best. Its support: lesson 203, line 10: «Fish that are small enough to fit in another fish's mouth may be eaten, so owners check how big each fish will grow before putting them together.», reached through a sentence linked to the one the question matched. What matched: the same action «fit» (+3); the same circumstance (+2). · the question and its options parsed, with trees and pragmatics
Exam question 4 · formal language · wrong ✗
Select the response consistent with the established facts concerning the clownfish represented in the film concerning Nemo.
- 1. The species exists solely in animated films — ← Mova's choice · no support
- 2. The species requires no water whatsoever — no support
- 3. The species thrives in cold tap water — no support
- 4. The species inhabits warm sea water and is unsuited to a cold freshwater tank — ✓ 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
This page in Markdown → https://md.mova.elamur.ai/free/en/school-run/biology/203-the-fish-tank-water-gills-heaters-and-the-right-neighbours/