diff --git a/README.md b/README.md
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--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # SwiftUITodo
 
-SwiftUITodo is an example to-do list application using [SwiftUI](https://developer.apple.com/xcode/swiftui/) which is first introduced in WWDC19 keynote.
+SwiftUITodo is an example to-do list application using [SwiftUI](https://developer.apple.com/xcode/swiftui/) which was first introduced in WWDC19 keynote.
 
 ![screenshot](https://user-images.githubusercontent.com/931655/58843349-f6dbf400-8626-11e9-8227-fbd369c29515.png)