Hybaser

public interface LogInterface {
    void log();
}

public class FileLogger: LogInterface {
	public void log() {Console.WriteLine("logged to file");}
}

public class User {

Hybaser

public class FileLogger {
	public void log() {Console.WriteLine("logged to file");}
}

public class User {
	FileLogger logger = new FileLogger();
	
    public void saveUser() {
		//... save operations

Hybaser

public interface DailyWork {
    void WakeUp();
    void FeedDog();
}

public interface WeekdayWork {
    void GoWork();
}

public class WeekDays: DailyWork, WeekdayWork {

Hybaser

public interface DailyWork {
    void WakeUp();
    void FeedDog();
    void GoWork();
}

public class WeekDays: DailyWork {
    public void WakeUp() {
        //...
    }

Hybaser

public interface Human {
    void Eat();
}

public interface IRunnable {
    void Run();
}

public class Man : Human, IRunnable {
    public void Eat() {

Hybaser

public interface Human {
    void Eat();
    void Run();
}

public class Man : Human {
    public void Eat() {
        //eat code
    };

Hybaser

public class Computer {
    public int cpuCount;
    public int ramSize;
    //....
}

public class Notebook : Computer {
    private bool batteryType;
    private int screenSize;
    //....

Hybaser

public class Currency {

    private string currencyCode;
    private string currencyName;
    private double currencyValue;

    public string getCurrencyCode() {
        return currencyCode;
    }

Hybaser

public class CurrencyCodes {

    private string currencyCode;
    private string currencyName;
    private double currencyValue;

    public string getCurrencyCode() {
        return currencyCode;
    }