Update README.md

Author: veler

Diff for: Tools/CtrlHelpEditor/README.md

@@ -9,12 +9,12 @@ With this tool, you can add or edit an app to be supported by `CtrlHelp`, along
 1. Clone this repository
 1. Run `CtrlHelpEditor.exe` (requires [.NET 8.0 Desktop Runtime](https://dotnet.microsoft.com/en-us/download/dotnet/8.0))
 
-To edit and existing app:
+To edit an existing app:
 1. Select `File > Open` and select the file [Shortcuts/apps.json](../../Shortcuts/apps.json).
 1. Double click the app you want to edit.
 
 To add a new app:
 1. Select `File > New`. Fill in the fields.
 1. When saving (`File > Save`), select the file [Shortcuts/apps.json](../../Shortcuts/apps.json).
 
-Finally, when your change is done, you can create a [pull request](https://github.com/veler/CtrlHelpApp/pulls) to submit your change to CtrlHelp's author.
+Finally, when your change are done, you can create a [pull request](https://github.com/veler/CtrlHelpApp/pulls) to submit your change to CtrlHelp's author.