diff --git a/curriculum/challenges/english/blocks/lecture-working-with-backgrounds-and-borders/672b98be592cfb451f651451.md b/curriculum/challenges/english/blocks/lecture-working-with-backgrounds-and-borders/672b98be592cfb451f651451.md
index 5c182884b03..39ae54fbbc9 100644
--- a/curriculum/challenges/english/blocks/lecture-working-with-backgrounds-and-borders/672b98be592cfb451f651451.md
+++ b/curriculum/challenges/english/blocks/lecture-working-with-backgrounds-and-borders/672b98be592cfb451f651451.md
@@ -59,7 +59,7 @@ background: radial-gradient(shape size at position, color-stop1, color-stop2, ..
 
 On the syntax, the `shape` specifies the shape of gradient which could be `circle` or `ellipse`.
 
-The `size` determines the size of the gradient's ending shape which could be `closest-side`, `closest-corner`, `farthest-side`, `farthest-corner`, `contain`, or `cover`.
+The `size` determines the size of the gradient's ending shape which could be `closest-side`, `closest-corner`, `farthest-side` or `farthest-corner`.
 
 `position` determines the position of the gradient's center which could be specified using keywords (such as `center`, `top left`, `bottom right`) or precise values (such as `50% 50%`, `10px 20px`).