Docs: Fix typo in MeshSurfaceSampler page.

docs/examples/en/math/MeshSurfaceSampler.html

@@ -74,7 +74,7 @@
 
 		<h3>[method:this sample]( [param:Vector3 targetPosition], [param:Vector3 targetNormal], [param:Color targetColor] )</h3>
 		<p>
-		Selects a random point on the surface of the input geometry, returning the position and optional the normal vector and color at that point. Time complexity is <i>O(log n)</i> for a surface with <i>n</i> faces.</i></p>
+		Selects a random point on the surface of the input geometry, returning the position and optionally the normal vector and color at that point. Time complexity is <i>O(log n)</i> for a surface with <i>n</i> faces.</i></p>
 
 		<h2>Source</h2>
 

docs/examples/zh/math/MeshSurfaceSampler.html

@@ -74,7 +74,7 @@
 
 		<h3>[method:this sample]( [param:Vector3 targetPosition], [param:Vector3 targetNormal], [param:Color targetColor] )</h3>
 		<p>
-		Selects a random point on the surface of the input geometry, returning the position and optional the normal vector and color at that point. Time complexity is <i>O(log n)</i> for a surface with <i>n</i> faces.</i></p>
+		Selects a random point on the surface of the input geometry, returning the position and optionally the normal vector and color at that point. Time complexity is <i>O(log n)</i> for a surface with <i>n</i> faces.</i></p>
 
 		<h2>Source</h2>