Update How-to-update-things.html

correct typo

docs/manual/en/introduction/How-to-update-things.html

@@ -24,7 +24,7 @@ scene.add( object1 ); //object1 and object2 will automatically update their matr
 			</code>
 		</div>
 
-		<p>However, if you know object will be static, you can disable this and update the transform matrix manually just when needed.</p>
+		<p>However, if you know the object will be static, you can disable this and update the transform matrix manually just when needed.</p>
 
 		<code>
 object.matrixAutoUpdate  = false;