Interface Example

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            var me = new Person();
            var myCar = new Car();

            #region carJourney

            GoOnAJourney(me, myCar);
            DriveSomewhere(me, myCar);

            #endregion

            #region airplane journey

            GoOnAJourney(me, new AirPlane());
            FlySomewhere(me, new AirPlane());

            #endregion
        }

        public static void GoOnAJourney(Person traveller, ITransportation transportation)
        {
            if (transportation.Passengers.Count < transportation.MaxCapacity)
            {
                transportation.Embark(traveller);

                transportation.Go();

                transportation.Disembark(traveller);
            }
            else { return; }
        }

        public static void DriveSomewhere(Person traveller, Car myCar)
        {
            if (myCar.Passengers.Count < myCar.MaxCapacity)
            {
                myCar.Embark(traveller);

                myCar.Go();

                myCar.Disembark(traveller);
            }
            else { return; }
        }

        public static void FlySomewhere(Person traveller, AirPlane plane)
        {
            if (plane.Passengers.Count < plane.MaxCapacity)
            {
                plane.Embark(traveller);

                plane.Go();

                plane.Disembark(traveller);
            }
            else { return; }
        }
    }

    public interface ITransportation
    {
        List<Person> Passengers { get; }

        TimeSpan ExpectedJourneyDuration { get; }

        int MaxCapacity { get; }

        void Embark(Person personToBoard);

        void Disembark(Person personToDisembark);

        void Go();
    }

    public class Car : ITransportation
    {
        public TimeSpan ExpectedJourneyDuration { get; }

        public List<Person> Passengers { get; }

        public int MaxCapacity { get; }

        public Car()
        {
            ExpectedJourneyDuration = TimeSpan.FromMinutes(20);
            Passengers = new List<Person>();
            MaxCapacity = 4;
        }

        public void Disembark(Person personToDisembark)
        {
            throw new NotImplementedException();
        }

        public void Embark(Person personToBoard)
        {
            throw new NotImplementedException();
        }

        public void Go()
        {
            throw new NotImplementedException();
        }
    }

    public class AirPlane : ITransportation
{
        public TimeSpan ExpectedJourneyDuration
        {
            get
            {
                throw new NotImplementedException();
            }
        }

        public int MaxCapacity
        {
            get
            {
                throw new NotImplementedException();
            }
        }

        public List<Person> Passengers
        {
            get
            {
                throw new NotImplementedException();
            }
        }

        public void Disembark(Person personToDisembark)
        {
            throw new NotImplementedException();
        }

        public void Embark(Person personToBoard)
        {
            throw new NotImplementedException();
        }

        public void Go()
        {
            throw new NotImplementedException();
        }
    }
}