--- title: Earthquakes — a lesson of Mova's school · trees and pragmatics description: «Earthquakes», a lesson of the geography course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: Rocks along a crack in the crust, a fault, want to slide past each other but are stuck; the strain builds up for years until suddenly they slip, and the jol --- [Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/) [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/) / [Geography](https://md.mova.elamur.ai/free/en/corpora/school/geography/) / Earthquakes # Earthquakes Lesson 44 of the geography course of Mova's primary school: 17 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/geography/44-earthquakes/). - [0](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/0/) — Rocks along a crack in the crust, a fault, want to slide past each other but are stuck; the strain builds up for years until suddenly they slip, and the jolt shakes the ground: that is an earthquake. - [1](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/1/) — Bend a ruler between your hands: it bends and bends, then snaps, and your hands jump; the rocks store energy the same way and release it in seconds. - [2](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/2/) — The shaking spreads out as waves: fast P waves arrive first, slower S waves next, and rolling surface waves last, which do the most damage. - [3](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/3/) — Shaking ground rarely kills anyone by itself; falling buildings do, so the best protection is buildings designed to bend and sway instead of crack. - [4](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/4/) — Nobody can yet say on which day an earthquake will strike, but scientists can map where the risk is high and how strong the quakes there can be. - [5](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/5/) — An earthquake is the sudden shaking when rocks along a fault slip after strain has built up. - [6](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/6/) — The point underground where the rock slips is the focus, and the point on the surface right above it is the epicentre, where the shaking is usually strongest. - [7](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/7/) — Earthquakes send out fast P waves that push and pull, slower S waves that shake side to side, and surface waves that do most damage; a machine called a seismograph records them. - [8](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/8/) — Earthquake size is given by magnitude, and each step up means about 32 times more energy released. - [9](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/9/) — The strongest earthquake ever recorded was in Chile in 1960, magnitude about 9.5. - [10](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/10/) — In 1755 an earthquake, a tsunami and fires destroyed much of Lisbon, killing tens of thousands of people. - [11](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/11/) — Most earthquake deaths are caused by collapsing buildings, not by the shaking ground itself. - [12](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/12/) — Earthquake-proof buildings use steel frames, flexible joints and even rubber or sliding bases to soak up shaking. - [13](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/13/) — Scientists cannot predict the exact day of an earthquake, but they can map which places are at risk. - [14](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/14/) — Britain has hundreds of small earthquakes a year, but almost all are too weak to feel. - [15](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/15/) — After a big earthquake come many smaller aftershocks, sometimes for months or years. - [16](https://md.mova.elamur.ai/free/en/corpora/school/geography/44-earthquakes/16/) — In an earthquake, people are taught to drop to the floor, take cover under a sturdy table and hold on until the shaking stops. - ← previous: [Moving continents: from Pangaea to today](https://md.mova.elamur.ai/free/en/corpora/school/geography/43-moving-continents-from-pangaea-to-today/) - next →: [Tsunamis](https://md.mova.elamur.ai/free/en/corpora/school/geography/45-tsunamis/) - ↑ back to [Geography](https://md.mova.elamur.ai/free/en/corpora/school/geography/)