diff --git a/2-ui/1-document/09-size-and-scroll/article.md b/2-ui/1-document/09-size-and-scroll/article.md
index 04fef202..5db8badd 100644
--- a/2-ui/1-document/09-size-and-scroll/article.md
+++ b/2-ui/1-document/09-size-and-scroll/article.md
@@ -104,7 +104,7 @@ For our sample element:
 ````smart header="Geometry properties are zero/null for elements that are not displayed"
 Geometry properties are calculated only for displayed elements.
 
-If an element (or any of its ancestors) has `display:none` or is not in the document, then all geometry properties are zero (or `null` if that's `offsetParent`).
+If an element (or any of its ancestors) has `display:none` or is not in the document, then all geometry properties are zero (or `null` for `offsetParent`).
 
 For example, `offsetParent` is `null`, and `offsetWidth`, `offsetHeight` are `0` when we created an element, but haven't inserted it into the document yet, or it (or it's ancestor) has `display:none`.