use React nested route, Home is the parent and News is the child. under root directory,there is "src" folder, in "src", is "pages" folder, in "pages", are "Home" and "News" folder. In "News", there is index.js:

Directory Structure :

| src/
| -- pages/
| ----- Home/
| --------index.js
| ----- News/
| --------index.js
| -- App.js

News/index.js

import React from 'react'

export default class News extends React.Component {
    render(){
        return( 
            <div style={{backgroundColor:'green',padding:10}}>
                this is content of child subcomponent
            </div>
        )
    }
}

Home/index.js

import React from 'react'

import {BrowserRouter as Router,Route,Routes} from 'react-router-dom'

import News from '../News'  

export default class Home extends React.Component {
    render(){
        return(
            
            <div style={{backgroundColor:'skyblue',padding:10}}>
                home
                <Routes>
                    <Route path = '/home/news' element={<News/>}></Route>
                </Routes>
            </div>
            
        
    )
}

src/App.js

import './App.css';


import {BrowserRouter as Router,Route,Link,Routes} from 'react-router-dom'
import {Button} from 'antd-mobile'


import Home from './pages/Home'
import CityList from './pages/CityList'
import React from 'react';

function App() {
  return (
    <Router>
       <div className="App">
          <ul>
             <li><Link to='/home'>home</Link></li>
             <li><Link to='/citylist'>citylist</Link></li>
          </ul>
  
          <Routes>
              <Route path='/home' element={<Home/>}/>
              <Route path='/citylist' element = {<CityList/>}/>
          </Routes>
       </div>
    </Router>

  );
}

export default App;

when the program running, as the web site is http://localhost:3000/home,it is ok, but when I add news after the website, http://localhost:3000/home/news , the child component has not been shown correctly, that is no "this is content of child subcomponent" displayed, could you please tell me why and how to solve it.