Update line 742 Q.23

Author: Mohammed-Nasif

README.md

@@ -739,7 +739,7 @@ console.log(num);
 
 With the `var` keyword, you can declare multiple variables with the same name. The variable will then hold the latest value.
 
-You cannot do this with `let` or `const` since they couldn't be redeclared.
+You cannot do this with `let` or `const` since they're block-scoped and therefore can't be redeclared.
 
 </p>
 </details>