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en/src/why-exercise.md

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+<div align="center">
+    <img height="150" src="https://github.com/sunface/rust-by-practice/blob/master/assets/logo.png?raw=true">
+</div>
+    
+<p align="center">Practice Rust with challenging examples, exercises and projects</p>
+    
+<div align="center">
+
+[![Stars Count](https://img.shields.io/github/stars/sunface/rust-by-practice?style=flat)](https://github.com/sunface/rust-by-practice/stargazers) [![Forks Count](https://img.shields.io/github/forks/sunface/rust-by-practice.svg?style=flat)](https://github.com/naaive/orange/network/members)
+[![LICENSE](https://img.shields.io/badge/license-mit-green?style=flat)](https://github.com/sunface/rust-by-practice/blob/master/LICENSE)
+</div>
+
+This book was designed for easily diving into and get skilled with Rust, and it's very easy to use: All you need to do is to make each exercise compile without ERRORS and Panics !
+
+
+## Reading online
+
+- [English](https://practice.rs)
+- [简体中文](https://zh.practice.rs)
+
+
+## Running locally
+
+We use [mdbook](https://rust-lang.github.io/mdBook/) building our exercises. You can run locally with below steps:
+```shell
+$ cargo install mdbook
+$ cd rust-by-practice && mdbook serve 
+```
+
+## Features
+
+Part of our examples and exercises are borrowed from [Rust By Example](https://github.com/rust-lang/rust-by-example), thanks for your great works!
+
+Although they are so awesome, we have our own secret weapons :)
+
+- There are three parts in each chapter: examples, exercises and practices
+
+- Besides examples, we have `a lot of exercises`, you can Read, Edit and Run them ONLINE
+
+- Covering nearly all aspects of Rust, such as async/await, threads, sync primitives, optimizing, standard libraries, tool chain, data structures and algorithms etc.
+
+- Every exercise has its own solutions
+
+- The overall difficulties are a bit higher and from easy to super hard: easy 🌟 medium 🌟🌟 hard 🌟🌟🌟 super hard 🌟🌟🌟🌟
+
+**What we want to do is fill in the gap between learning and getting started with real projects.**