Update reactivity-fundamentals.md (#2442)

Author: draqist

src/guide/essentials/reactivity-fundamentals.md

@@ -194,9 +194,9 @@ If you are not using SFC, you can still use Composition API with the [`setup()`]
 
 You might be wondering why we need refs with the `.value` instead of plain variables. To explain that, we will need to briefly discuss how Vue's reactivity system works.
 
-When you use a ref in the template, and changes the ref's value later, Vue automatically detects the change and updates the DOM accordingly. This is made possible with a dependency-tracking based reactivity system. When a component is rendered for the first time, Vue **tracks** every ref that was used during the render. Later on, when a ref is mutated, it will **trigger** re-render for components that are tracking it.
+When you use a ref in a template, and change the ref's value later, Vue automatically detects the change and updates the DOM accordingly. This is made possible with a dependency-tracking based reactivity system. When a component is rendered for the first time, Vue **tracks** every ref that was used during the render. Later on, when a ref is mutated, it will **trigger** a re-render for components that are tracking it.
 
-In standard JavaScript, there is no way to detect the access or mutation of plain variables. But we can intercept a property's get and set operations.
+In standard JavaScript, there is no way to detect the access or mutation of plain variables. However, we can intercept the get and set operations of an object's properties using getter and setter methods.
 
 The `.value` property gives Vue the opportunity to detect when a ref has been accessed or mutated. Under the hood, Vue performs the tracking in its getter, and performs triggering in its setter. Conceptually, you can think of a ref as an object that looks like this: