Document multiple ways to insert comments in JSX

docs/02.1-jsx-in-depth.md

@@ -161,10 +161,20 @@ var content = Container(null, window.isLoggedIn ? Nav(null) : Login(null));
 
 ### Comments
 
-It's easy to add comments within your JSX; they're just JS expressions:
+It's easy to add comments within your JSX; they're just JS expressions. You just need to be careful to put `{}` around the comments when you are within the children section of a tag.
 
 ```javascript
-var content = <Container>{/* this is a comment */}<Nav /></Container>;
+var content = (
+  <Nav>
+    {/* child comment, put {} around */}
+    <Person
+      /* multi
+         line
+         comment */
+      name={window.isLoggedIn ? window.name : ''} // end of line comment
+    />
+  </Nav>
+);
 ```