Missing noun in css-view-transitions-1/Overview.bs

The previous version of this sentence was missing a noun.

The sentence at the start of the paragraph makes it clear what's missing.

Author: ccouzens

css-view-transitions-1/Overview.bs

@@ -272,7 +272,7 @@ urlPrefix: https://wicg.github.io/navigation-api/; type: interface;
 
 	If the ''::view-transition-group()'' has a corresponding element in the "new" states,
 	the browser keeps the properties copied over to the ''::view-transition-group()'' in sync with the DOM element in the "new" state.
-	If the ''::view-transition-group()'' has a corresponding both in the "old" and "new" state,
+	If the ''::view-transition-group()'' has corresponding elements both in the "old" and "new" state,
 	and the property being copied is interpolatable,
 	the browser also sets up a default animation to animate the property smoothly.