Fix comma

docs/refactor/02-displaying-data.md

@@ -53,7 +53,7 @@ setInterval(function() {
 
 View the finished code in a web browser and type your name into the text field. Notice that React is only changing the time string in the UI -- any input you put in the text field remains, even though you haven't written any code to manage this behavior. React figures it out for you and does the right thing.
 
-The way it is able to figure this out is that React does not directly manipulate the DOM, **it uses a fast, internal mock DOM to perform diffs and computes the most efficient DOM mutation for you.**
+The way it is able to figure this out is that React does not directly manipulate the DOM. **It uses a fast, internal mock DOM to perform diffs and computes the most efficient DOM mutation for you.**
 
 The inputs to this component are called `props` -- short for "properties". They're passed as attributes in JSX syntax. You should think of these as immutable within the component, that is, **never write to this.props**.
 
@@ -75,4 +75,4 @@ JSX is very small; the "hello, world" example above uses every feature of JSX. T
 
 JSX is similar to HTML, but not exactly the same. See [JSX gotchas](./02.2-jsx-gotchas.html) for some key differences.
 
-The easiest way to get started with JSX is to use the in-browser `JSXTransformer`, but in production you'll want to precompile your code using our command-line [react-tools](http://npmjs.org/package/react-tools) package.
+The easiest way to get started with JSX is to use the in-browser `JSXTransformer`, but in production you'll want to precompile your code using our command-line [react-tools](http://npmjs.org/package/react-tools) package.