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builtins/amp-img.md

@@ -14,28 +14,25 @@ See the License for the specific language governing permissions and
 limitations under the License.
 -->
 
-### <a name="amp-img"></a> `amp-img`
+## <a name="amp-img"></a> `amp-img`
 
 A runtime-managed replacement for the HTML `img` tag.
 
-#### Behavior
+### Behavior
 
-The runtime may choose to delay or prioritize resource loading based on the viewport position, system resources, connection bandwidth, or other factors. The `amp-img` components allows the runtime to effectively manage image resources this way.
+The runtime may choose to delay or prioritize resource loading based on the viewport position, system resources, connection bandwidth, or other factors. The `amp-img` component allows the runtime to effectively manage image resources.
 
-`amp-img` components, like all externally fetched AMP resources, must be given an
-explicit size (as in width / height) in advance, so that the aspect ratio can be known without fetching the image. Actual layout behavior is determined by the layout attribute. If the resource requested by the `amp-img` component fails to load, the space will be blank. A placeholder background color or other visual can be set using CSS selector and style on the element itself.
+`amp-img` components, like all externally fetched AMP resources, must be given an explicit `width` and `height` in advance, so that the aspect ratio can be known without fetching the image. Actual layout behavior is determined by the `layout` attribute. If the resource requested by the `amp-img` component fails to load, the space will be blank. A placeholder background color or other visual can be set using a CSS selector and style on the element itself.
 
 The `amp-img` includes attributes for denoting attribution via the attribution attribute.
 
-Additional image features like captions can be implemented with standard HTML - using the `figure` and `figcaption` elements, for example.
+Additional image features like captions can be implemented with standard HTML, such as the `figure` and `figcaption` elements.
 
-#### Attributes
+### Attributes
 
 **src**
 
-Similar to the `src` attribute on the `img` tag. The value must be a URL that
-points to a publicly-cacheable image file. Cache providers may rewrite these
-URLs when ingesting AMP files to point to a cached version of the image.
+Similar to the `src` attribute on the `img` tag. The value must be a URL that points to a publicly-cacheable image file. Cache providers may rewrite these URLs when ingesting AMP files to point to a cached version of the image.
 
 **srcset**
 
@@ -47,13 +44,13 @@ A string of alternate text, similar to the `alt` attribute on `img`.
 
 **attribution**
 
-A string that indicates the attribution of the image. E.g. `attribution="CC courtesy of Cats on Flicker"`
+A string that indicates the attribution of the image, e.g., `attribution="CC courtesy of Cats on Flicker"`
 
 
-#### Styling
+### Styling
+
+`amp-img` can be styled directly via CSS properties. Setting a grey background placeholder, for example, could be achieved via:
 
-`amp-img` can be styled directly via CSS properties. Setting a grey background
-placeholder for example could be achieved via:
 ```css
 amp-img {
   background-color: grey;