diff --git a/Car.java b/Car.java
new file mode 100644
index 0000000..3b6e6bf
--- /dev/null
+++ b/Car.java
@@ -0,0 +1,35 @@
+public class Car extends Vehicle {
+
+  private final int seats;
+
+  public Car(String make, String model, Engine engine, int seats) {
+    super(make, model, engine);
+    this.seats = seats;
+  }
+
+  public int getSeats() {
+    return seats;
+  }
+
+  public void doATurboBoost() {
+    speedInKmh *= 2;
+    System.out.println(
+        getMake()
+            + " "
+            + getModel()
+            + " macht einen Turboboost und beschleunigt auf "
+            + speedInKmh
+            + " km/h");
+  }
+
+  public String toString() {
+    return getMake()
+        + " "
+        + getModel()
+        + " ("
+        + getEngine().getDescription()
+        + ", "
+        + seats
+        + " Sitzplaetze)";
+  }
+}
diff --git a/Engine.java b/Engine.java
index ffc88a7..5f2aea9 100644
--- a/Engine.java
+++ b/Engine.java
@@ -4,7 +4,7 @@ public enum Engine {
   GAS("Gas"),
   ELECTRO("Elektro");
 
-  private String description;
+  private final String description;
 
   Engine(String description) {
     this.description = description;
diff --git a/Exercise.java b/Exercise.java
index f3b80e5..8255262 100644
--- a/Exercise.java
+++ b/Exercise.java
@@ -3,10 +3,19 @@ public class Exercise {
   public static void main(String[] args) {
     System.out.println("Anzahl Fahrzeuge: " + Vehicle.getNumberOfVehicles());
 
-    Vehicle vehicle1 = new Vehicle("Porsche", "911", Engine.ELECTRO);
-    Vehicle vehicle2 = new Vehicle("MAN", "TGX", Engine.DIESEL);
-    Vehicle vehicle3 = new Vehicle("Opel", "Zafira Life", Engine.DIESEL);
+    Car car1 = new Car("Porsche", "911", Engine.ELECTRO, 2);
+    Truck truck1 = new Truck("MAN", "TGX", Engine.DIESEL, 20);
+    Car car2 = new Car("Opel", "Zafira Life", Engine.DIESEL, 7);
 
     System.out.println("Anzahl Fahrzeuge: " + Vehicle.getNumberOfVehicles());
+
+    System.out.println(car1.toString());
+    System.out.println(truck1.toString());
+    System.out.println(car2.toString());
+
+    car1.accelerate(50);
+    truck1.transform();
+    car1.doATurboBoost();
+    truck1.transform();
   }
 }
diff --git a/Truck.java b/Truck.java
new file mode 100644
index 0000000..ae110f6
--- /dev/null
+++ b/Truck.java
@@ -0,0 +1,32 @@
+public class Truck extends Vehicle {
+
+  private final int cargo;
+  private boolean isTransformed;
+
+  public Truck(String make, String model, Engine engine, int cargo) {
+    super(make, model, engine);
+    this.cargo = cargo;
+  }
+
+  public int getCargo() {
+    return cargo;
+  }
+
+  public boolean isTransformed() {
+    return isTransformed;
+  }
+
+  public void transform() {
+    if (isTransformed) {
+      System.out.println(
+          getMake() + " " + getModel() + " verwandelt sich in einen Lastwagen zurueck");
+    } else {
+      System.out.println(getMake() + " " + getModel() + " verwandelt sich in einen Autobot");
+    }
+    isTransformed = !isTransformed;
+  }
+
+  public String toString() {
+    return getMake() + " " + getModel() + " (" + getEngine().getDescription() + ", " + cargo + "t)";
+  }
+}
diff --git a/Vehicle.java b/Vehicle.java
index 238f0bf..216451f 100644
--- a/Vehicle.java
+++ b/Vehicle.java
@@ -2,7 +2,7 @@ public class Vehicle {
 
   private String make;
   private String model;
-  private double speedInKmh;
+  protected double speedInKmh;
   private Engine engine;
   private static int numberOfVehicles;