Update site/content/tutorial/02-reactivity/04-updating-arrays-and-objects/text.md

Co-authored-by: Ben McCann <322311+benmccann@users.noreply.github.com>

site/content/tutorial/02-reactivity/04-updating-arrays-and-objects/text.md

@@ -2,7 +2,7 @@
 title: Updating arrays and objects
 ---
 
-Svelte's reactivity is triggered by assignments. Methods that mutate arrays/objects internally will not trigger updates by themselves.
+Svelte's reactivity is triggered by assignments. Methods that mutate arrays or objects will not trigger updates by themselves.
 
 In this example, clicking the "Add a number" button calls the `addNumber` function, which appends a number to the array but doesn't trigger the recalculation of `sum`.