--- title: Water safety and the ocean — a lesson of Mova's school · trees and pragmatics description: «Water safety and the ocean», a lesson of the physics course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: The deeper you go in water, the harder it presses, because more and more water is piled up above you; you feel it in your ears at the bottom of --- [Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/) [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/) / [Physics](https://md.mova.elamur.ai/free/en/corpora/school/physics/) / Water safety and the ocean # Water safety and the ocean Lesson 13 of the physics course of Mova's primary school: 15 sentences, each with its syntax tree and pragmatics. The lessons are written for Mova, and their agreed trees are part of Mova corpus 0.4 (CC BY-SA 4.0). How Mova does on its tests: [the lesson at school](https://md.mova.elamur.ai/free/en/school-run/physics/13-water-safety-and-the-ocean/). - [0](https://md.mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/0/) — The deeper you go in water, the harder it presses, because more and more water is piled up above you; you feel it in your ears at the bottom of a deep pool. - [2](https://md.mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/2/) — Water also holds up most of your weight, so a friend feels light in the pool, and a boat stays steady only while its weight is kept low. - [3](https://md.mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/3/) — Knowing how water behaves keeps people safe: thin ice, rip currents and a person quietly struggling in the water are real dangers, and the safe move is always to call an adult or a lifeguard. - [4](https://md.mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/4/) — Thick, very cold ice can carry a heavy lorry across a frozen lake in the far north, but ice on ponds at home can look solid and be far too thin, so never walk on it. - [5](https://md.mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/5/) — Every 10 metres of seawater presses as hard as the whole air above us, so divers' ears hurt as they go deeper. - [6](https://md.mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/6/) — Divers equalise their ears (even out the push inside them, for example by pinching the nose and blowing gently) as they go down, and come up slowly, because shooting up fast can badly hurt them. - [7](https://md.mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/7/) — Deep-sea fish live under enormous pressure because their bodies are full of water, which hardly squashes and is pressed evenly from all sides. - [8](https://md.mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/8/) — Some deep-sea fish brought up quickly are hurt because gas inside them grows. - [10](https://md.mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/10/) — A person drowning often cannot wave or shout; they bob, gasping, with the head tilted back, because all their effort goes into breathing. - [11](https://md.mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/11/) — If someone in the water looks wrong, call an adult or a lifeguard at once and never jump in after them yourself. - [12](https://md.mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/12/) — A rip current is water piled up by waves rushing back out to sea through a narrow channel. - [14](https://md.mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/14/) — A canoe tips over if someone stands up suddenly, because a boat is steady only while its weight is low, so keep low and in the middle. - [15](https://md.mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/15/) — Polystyrene, the light white foam used in packing, is mostly trapped air bubbles, so it floats almost on top of the water, and bits of it pollute the sea for years. - [16](https://md.mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/16/) — A goldfish stays at one depth by keeping just the right amount of gas in its swim bladder, and a fish floating on its side may have a sick swim bladder. - [17](https://md.mova.elamur.ai/free/en/corpora/school/physics/13-water-safety-and-the-ocean/17/) — In a pool the water holds up most of your weight, because our bodies are about as heavy as water for their size, which makes swimming good for sore joints. - ← previous: [Floating in the real world: ice, submarines and balloons](https://md.mova.elamur.ai/free/en/corpora/school/physics/12-ice-submarines-and-balloons/) - next →: [The air presses on everything](https://md.mova.elamur.ai/free/en/corpora/school/physics/14-the-air-presses-on-everything/) - ↑ back to [Physics](https://md.mova.elamur.ai/free/en/corpora/school/physics/)