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app/src/test/java/com/example/leeyuanair/englishhelper/ExampleUnitTest.java

@@ -0,0 +1,15 @@
+package com.example.leeyuanair.englishhelper;
+
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+/**
+ * To work on unit tests, switch the Test Artifact in the Build Variants view.
+ */
+public class ExampleUnitTest {
+    @Test
+    public void addition_isCorrect() throws Exception {
+        assertEquals(4, 2 + 2);
+    }
+}