diff --git a/.github/workflows/hello.yml b/.github/workflows/hello.yml
index d0fc4e6..2a8b057 100644
--- a/.github/workflows/hello.yml
+++ b/.github/workflows/hello.yml
@@ -10,6 +10,8 @@ jobs:
   build:
     runs-on: ubuntu-latest
     strategy:
+      fail-fast: true
+      max-parallel: 0
       matrix: 
         hello: [AAA, CCC, EEE]
         include:
@@ -23,4 +25,7 @@ jobs:
     - uses: actions/checkout@v2
     
     - name: Run a one-line script
-      run: echo HELLO ${{matrix.hello}} and BYE ${{matrix.bye}}
+      run: |
+        echo HELLO ${{matrix.hello}} and BYE ${{matrix.bye}}
+        sleep 20
+        echo HELLO ${{matrix.hello}} and BYE ${{matrix.bye}}