diff --git a/src/main/java/Duke.java b/src/main/java/Duke.java
index 522872cc6d..a4c3039597 100644
--- a/src/main/java/Duke.java
+++ b/src/main/java/Duke.java
@@ -17,58 +17,65 @@ public static void main(String[] args) {
 
         while (!command.startsWith("bye")) {
 
-            if (command.startsWith("list")) {
-                System.out.println("____________________________________________________________");
-                System.out.println(" Here are the tasks in your list:");
-                int counter = 0;
-                while (counter != list.size()) {
-                    counter++;
-                    System.out.println(" " + counter + "." + list.get(counter - 1).toString());
+            try{
+                if (command.startsWith("list")) {
+                    System.out.println("____________________________________________________________");
+                    System.out.println(" Here are the tasks in your list:");
+                    int counter = 0;
+                    while (counter != list.size()) {
+                        counter++;
+                        System.out.println(" " + counter + "." + list.get(counter - 1).toString());
+                    }
+                    System.out.println("____________________________________________________________");
+                } else if (command.startsWith("mark")) {
+                    list.get(Integer.valueOf(command.split(" ")[1]) - 1).markAsDone();
+                    System.out.println("____________________________________________________________");
+                    System.out.println(" Nice! I've marked this task as done:");
+                    System.out.println("  " + list.get(Integer.valueOf(command.split(" ")[1]) - 1).toString());
+                    System.out.println("____________________________________________________________");
+                } else if (command.startsWith("todo")) {
+                    if (command.split(" ", 2).length == 1) {
+                        throw new DukeException("☹ OOPS!!! The description of a todo cannot be empty.");
+                    }
+                    ToDo newToDo = new ToDo(command.split(" ", 2)[1]);
+                    list.add(newToDo);
+                    System.out.println("____________________________________________________________");
+                    System.out.println(" Got it. I've added this task:");
+                    System.out.println("   " + newToDo.toString());
+                    System.out.println(" Now you have " + list.size() + " tasks in the list.");
+                    System.out.println("____________________________________________________________");
+                } else if (command.startsWith("deadline")) {
+                    String deadline = command.split(" /by ", 2)[1];
+                    String name = command.split(" /by ", 2)[0].split(" ", 2)[1];
+                    Deadline newDeadline = new Deadline(deadline, name);
+                    list.add(newDeadline);
+                    System.out.println("____________________________________________________________");
+                    System.out.println(" Got it. I've added this task:");
+                    System.out.println("   " + newDeadline.toString());
+                    System.out.println(" Now you have " + list.size() + " tasks in the list.");
+                    System.out.println("____________________________________________________________");
+                } else if (command.startsWith("event")) {
+                    String startTime = command.split(" /from ", 2)[1]
+                            .split(" /to ", 2)[0];
+                    String endTime = command.split(" /to ", 2)[1];
+                    String name = command.split(" /from ", 2)[0].split(" ", 2)[1];
+                    Event newEvent = new Event(name, startTime, endTime);
+                    list.add(newEvent);
+                    System.out.println("____________________________________________________________");
+                    System.out.println(" Got it. I've added this task:");
+                    System.out.println("   " + newEvent.toString());
+                    System.out.println(" Now you have " + list.size() + " tasks in the list.");
+                    System.out.println("____________________________________________________________");
+                } else {
+                    throw new DukeException("☹ OOPS!!! I'm sorry, but I don't know what that means :-(");
                 }
+            } catch (DukeException e) {
                 System.out.println("____________________________________________________________");
-            } else if (command.startsWith("mark")) {
-                list.get(Integer.valueOf(command.split(" ")[1]) - 1).markAsDone();
-                System.out.println("____________________________________________________________");
-                System.out.println(" Nice! I've marked this task as done:");
-                System.out.println("  " + list.get(Integer.valueOf(command.split(" ")[1]) - 1).toString());
-                System.out.println("____________________________________________________________");
-            } else if (command.startsWith("todo")) {
-                ToDo newToDo = new ToDo(command.split(" ", 2)[1]);
-                list.add(newToDo);
-                System.out.println("____________________________________________________________");
-                System.out.println(" Got it. I've added this task:");
-                System.out.println("   " + newToDo.toString());
-                System.out.println(" Now you have " + list.size() + " tasks in the list.");
-                System.out.println("____________________________________________________________");
-            } else if (command.startsWith("deadline")) {
-                String deadline = command.split(" /by ", 2)[1];
-                String name = command.split(" /by ", 2)[0].split(" ", 2)[1];
-                Deadline newDeadline = new Deadline(deadline, name);
-                list.add(newDeadline);
-                System.out.println("____________________________________________________________");
-                System.out.println(" Got it. I've added this task:");
-                System.out.println("   " + newDeadline.toString());
-                System.out.println(" Now you have " + list.size() + " tasks in the list.");
-                System.out.println("____________________________________________________________");
-            } else if (command.startsWith("event")) {
-                String startTime = command.split(" /from ", 2)[1]
-                        .split(" /to ", 2)[0];
-                String endTime = command.split(" /to ", 2)[1];
-                String name = command.split(" /from ", 2)[0].split(" ", 2)[1];
-                Event newEvent = new Event(name, startTime, endTime);
-                list.add(newEvent);
-                System.out.println("____________________________________________________________");
-                System.out.println(" Got it. I've added this task:");
-                System.out.println("   " + newEvent.toString());
-                System.out.println(" Now you have " + list.size() + " tasks in the list.");
-                System.out.println("____________________________________________________________");
-            } else {
-                list.add(new Task(command));
-                System.out.println("____________________________________________________________");
-                System.out.println(" added: " + command);
+                System.out.println(" " + e.getMessage());
                 System.out.println("____________________________________________________________");
+            } finally {
+                command = userInput.nextLine();
             }
-            command = userInput.nextLine();
         }
 
         System.out.println("____________________________________________________________");
diff --git a/src/main/java/DukeException.java b/src/main/java/DukeException.java
new file mode 100644
index 0000000000..c858d79e91
--- /dev/null
+++ b/src/main/java/DukeException.java
@@ -0,0 +1,5 @@
+public class DukeException extends Exception{
+    public DukeException(String message) {
+        super(message);
+    }
+}