diff --git a/HFUTCourseSimulation/Dialog/Simulator.xaml.cs b/HFUTCourseSimulation/Dialog/Simulator.xaml.cs
index 7af8109..8e89aaf 100644
--- a/HFUTCourseSimulation/Dialog/Simulator.xaml.cs
+++ b/HFUTCourseSimulation/Dialog/Simulator.xaml.cs
@@ -126,6 +126,18 @@ namespace HFUTCourseSimulation.Dialog {
             Grid.SetRow(cornerLabel, 0);
             Grid.SetRowSpan(cornerLabel, 2);
             uiCoreGrid.Children.Add(cornerLabel);
+            // Add chessboard
+            for (int week = 1; week <= WEEK_NAMES.Length; ++week) {
+                for (int index = 1; index <= CurrentSemester.indexCount; ++index) {
+                    if ((week + index) % 2 != 0) continue;
+
+                    var chessboard = new Rectangle();
+                    chessboard.Fill = new SolidColorBrush(Color.FromArgb(10, 0, 0, 0));
+                    Grid.SetColumn(chessboard, week - 1 + 1);
+                    Grid.SetRow(chessboard, index - 1 + 2);
+                    uiCoreGrid.Children.Add((chessboard));
+                }
+            }
 
             // Render for week 1
             currentWeek = 1;