Update README.md

Author: roberto-butti

README.md

@@ -458,16 +458,18 @@ $fruits = Block::make($fruitsArray)
     ->throwOnMissingKey();
 
 $nothing = $fruits->get("a-missing-key"); // throws exception
+```
 
+You can also pass your own exception class (must extend `\Throwable`).
 
+```php
 $fruits->throwOnMissingKey(
     MyMissingKeyException::class,
-    "The key in the configuration JSON file doens't exist?"
+    "The key in the JSON configuration file does not exist?"
 );
+$nothing = $fruits->get("a-missing-key"); // throws your custom exception
 ```
 
-You can also pass your own exception class (must extend `\Throwable`).
-
 #### Summary for the "missing key behavior"
 
 | Mode      | Result                               |