public class Program

{

    public static void Main()

    {

        var engine = new CarEngine();

        engine.Drive();

    }

}

​

public class CarEngine {

    private bool engineStarted  { set; get; }

    private int gear            { set; get; }

    private bool clutchIsDown   { set; get; }

    private void StartEngine() {

        if (this.engineStarted == false) {

            this.engineStarted = true;  

        }   

    }

    private void PressClutch() {

        if (this.clutchIsDown == false) {

            this.clutchIsDown = true;

        }

    }

    private void ChangeGearTo(int newGear) {

        if (gear != newGear){

            gear = newGear;

        }

    }

    private bool CanDrive() {

        return this.engineStarted;

    }

    public void Drive() {

        if (CanDrive() == false) {      

            StartEngine();

        }

        PressClutch();

        ChangeGearTo(1);

    }

}