Fix a typo

The infinitive form should be used.

Author: Stamo-Gochev

book/chapter-5/README.md

@@ -14,7 +14,7 @@ class App extends React.Component {
 };
 ```
 
-The result of this code is an input element that we can focus but can't change. It is never updated because we have a single source of truth - the `App`'s component state. To make the input works as expected we have to add an `onChange` handler and update the state (the single source of truth). Which will trigger a new rendering cycle and we will see what we typed.
+The result of this code is an input element that we can focus but can't change. It is never updated because we have a single source of truth - the `App`'s component state. To make the input work as expected we have to add an `onChange` handler and update the state (the single source of truth). Which will trigger a new rendering cycle and we will see what we typed.
 
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