Merge pull request #803 from adamcnaglich/patch-1

Added a missing comma

Author: iliakan

1-js/02-first-steps/02-structure/article.md

@@ -6,7 +6,7 @@ The first thing we'll study is the building blocks of code.
 
 Statements are syntax constructs and commands that perform actions.
 
-We've already seen a statement, `alert('Hello, world!')`, which shows the message "Hello world!".
+We've already seen a statement, `alert('Hello, world!')`, which shows the message "Hello, world!".
 
 We can have as many statements in our code as we want. Statements can be separated with a semicolon.