fix(curriculum): updates body-parser with explanation for extended config (#42740)

* fix: better explaination for body-parser extened config

* text readability by introducing line break

* grammer fixes

* fix: typo

Co-authored-by: Huyen Nguyen <25715018+huyenltnguyen@users.noreply.github.com>

Co-authored-by: Huyen Nguyen <25715018+huyenltnguyen@users.noreply.github.com>

curriculum/challenges/english/05-apis-and-microservices/basic-node-and-express/use-body-parser-to-parse-post-requests.md

@@ -26,9 +26,11 @@ As you can see, the body is encoded like the query string. This is the default f
 
 # --instructions--
 
-Install the `body-parser` module in your `package.json`. Then, `require` it at the top of the file. Store it in a variable named `bodyParser`. The middleware to handle urlencoded data is returned by `bodyParser.urlencoded({extended: false})`. Pass to `app.use()` the function returned by the previous method call. As usual, the middleware must be mounted before all the routes which need it.
+Install the `body-parser` module in your `package.json`. Then, `require` it at the top of the file. Store it in a variable named `bodyParser`. The middleware to handle urlencoded data is returned by `bodyParser.urlencoded({extended: false})`. Pass the function returned by the previous method call to `app.use()`. As usual, the middleware must be mounted before all the routes that depend on it.
 
-**Note:** `extended=false` is a configuration option that tells the parser to use the classic encoding. When using it, values can be only strings or arrays. The extended version allows more data flexibility, but it is outmatched by JSON.
+**Note:** `extended` is a configuration option that tells `body-parser` which parsing needs to be used. When `extended=false` it uses the classic encoding `querystring` library. When `extended=true` it uses `qs` library for parsing. 
+
+When using `extended=false`, values can be only strings or arrays. The object returned when using `querystring` does not prototypically inherit from the default JavaScript `Object`, which means functions like `hasOwnProperty`, `toString` will not be available. The extended version allows more data flexibility, but it is outmatched by JSON.
 
 # --hints--