using System;

public class Program

{

    public static void Main()

    {

        string heText = "פני התחלת הישיבה שלך {time}";

        string timePattern = "{time}";

        Console.WriteLine(heText.Replace(timePattern,DateTime.Now.ToString("dd/MM/yyyy")));

        var format = "{0} פני התחלת הישיבה שלך";

        Console.WriteLine(string.Format(format, DateTime.Now.ToString("dd/MM/yyyy")));

        string heText1 = "פני התחלת הישיבה שלך time";

        string timePattern1 = "time";

        Console.WriteLine(heText1.Replace(timePattern1,"\u200e" +DateTime.Now.ToString("dd/MM/yyyy")));

    }

}