--- title: Mountains, rivers and seas, and how the land is shaped — a lesson of Mova's school · trees and pragmatics description: «Mountains, rivers and seas, and how the land is shaped», a lesson of the world course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: The outer shell of the Earth is not one piece: it is broken into huge slabs called plates, which float on hot soft ro --- [Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/world/43-landforms/) [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/) / [World](https://md.mova.elamur.ai/free/en/corpora/school/world/) / Mountains, rivers and seas, and how th… # Mountains, rivers and seas, and how the land is shaped Lesson 43 of the world course of Mova's primary school: 20 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/world/43-landforms/). - [0](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/0/) — The outer shell of the Earth is not one piece: it is broken into huge slabs called plates, which float on hot soft rock and move a few centimetres a year, about as fast as your fingernails grow. - [1](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/1/) — Where two plates push together, the rock crumples and rises up as mountains over millions of years; the Himalayas, with Mount Everest, are still growing because India keeps pushing into Asia. - [2](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/2/) — Where plates grind or slip past each other, the ground shakes in an earthquake; where melted rock called magma finds a way up through cracks, it bursts out as lava from a volcano. - [3](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/3/) — Water shapes the land too: a river carries sand and stones that scrape its bed, and over thousands of years it cuts a deep valley shaped like the letter V; where it slows down near the sea, it drops its sand and mud and builds a delta. - [4](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/4/) — A lake is water resting in a hollow of the land, a sea is a part of the ocean partly closed by land, and a river is water flowing downhill in a channel from its source to its mouth. - [5](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/5/) — The Earth's outer shell is broken into huge plates that move very slowly. - [6](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/6/) — Mountains rise where plates push against each other for millions of years. - [7](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/7/) — Mount Everest in the Himalayas is the highest mountain on Earth, about 8,849 metres high. - [8](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/8/) — An earthquake is a sudden shaking of the ground when rocks along a crack slip. - [9](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/9/) — A volcano is an opening where melted rock, ash and gas come out from deep inside the Earth. - [10](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/10/) — Melted rock is called magma under the ground and lava when it comes out on the surface. - [11](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/11/) — A river starts at its source and ends at its mouth, where it flows into a sea, a lake or another river. - [12](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/12/) — Over thousands of years a river cuts a valley into the land with the sand and stones it carries. - [13](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/13/) — A delta is flat land built from the mud and sand a river drops where it slows down at its mouth. - [14](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/14/) — A lake is a body of water lying in a hollow of the land, and most lakes have fresh water. - [15](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/15/) — A sea is a part of the ocean that is partly surrounded by land. - [16](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/16/) — Wind, rain, ice and frost slowly break rocks into smaller pieces; this is called weathering. - [17](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/17/) — Water grows bigger when it freezes, so ice in a crack pushes the rock apart. - [18](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/18/) — Most earthquakes and volcanoes happen where plates meet. - [19](https://md.mova.elamur.ai/free/en/corpora/school/world/43-landforms/19/) — Some rock high in mountains formed long ago under the sea and was pushed up when plates collided, so it can hold shells of sea animals. - ← previous: [Continents and oceans](https://md.mova.elamur.ai/free/en/corpora/school/world/42-continents-and-oceans/) - next →: [The United States and its states](https://md.mova.elamur.ai/free/en/corpora/school/world/44-the-usa-and-its-states/) - ↑ back to [World](https://md.mova.elamur.ai/free/en/corpora/school/world/)