Added missing word

Author: Ovidiu Voicu

1-js/03-code-quality/06-polyfills/article.md

@@ -23,7 +23,7 @@ Actually, there are two parts in Babel:
 
 2. Second, the polyfill.
 
-    The transpiler rewrites the code, so syntax features are covered. But for new functions we need to a special script that implements them. JavaScript is a highly dynamic language, scripts may not just add new functions, but also modify built-in ones, so that they behave according to the modern standard.
+    The transpiler rewrites the code, so syntax features are covered. But for new functions we need to add a special script that implements them. JavaScript is a highly dynamic language, scripts may not just add new functions, but also modify built-in ones, so that they behave according to the modern standard.
 
     There's a term "polyfill" for scripts that "fill in" the gap and add missing implementations.