Add a missing word

Author: huyenltnguyen

2-ui/4-forms-controls/2-focus-blur/article.md

@@ -49,7 +49,7 @@ Your email please: <input type="email" id="input">
 </script>
 ```
 
-Modern HTML allows to do many validations using input attributes: `required`, `pattern` and so on. And sometimes they are just what we need. JavaScript can be used when we want more flexibility. Also we could automatically send the changed value to the server if it's correct.
+Modern HTML allows us to do many validations using input attributes: `required`, `pattern` and so on. And sometimes they are just what we need. JavaScript can be used when we want more flexibility. Also we could automatically send the changed value to the server if it's correct.
 
 
 ## Methods focus/blur