---
title: Crossing the river with one boat — a lesson of Mova's school · trees and pragmatics
description: «Crossing the river with one boat», a lesson of the lessons course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: The boat cannot cross empty, so after every trip across except the last one somebody must row it back.
---

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# Crossing the river with one boat

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Lesson 189 of the lessons course of Mova's primary school: 4 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).

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- [0](https://md.mova.elamur.ai/free/en/corpora/school/lessons/189-boat-crossings/0/) — The boat cannot cross empty, so after every trip across except the last one somebody must row it back.
- [1](https://md.mova.elamur.ai/free/en/corpora/school/lessons/189-boat-crossings/1/) — So each trip there and back moves one fewer than the boat holds; the last trip across takes a full boat.
- [2](https://md.mova.elamur.ai/free/en/corpora/school/lessons/189-boat-crossings/2/) — 11 people, a boat for 4: the first trip takes 4 across; each return and trip then adds 3 more: 4, 7, 10, 11.
- [3](https://md.mova.elamur.ai/free/en/corpora/school/lessons/189-boat-crossings/3/) — That is 4 trips across and 3 back, 7 crossings.

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