public static void Main()
string name = "Lorem Ipsum";
DateTime paidOn = new DateTime(2018, 1, 1, 12, 34, 56);
string normal = name + " paid " + price.ToString("0.00") + " on " + paidOn.ToString("yyyy-MM-dd HH:mm:ss");
string interpolated = $"{name} paid {price:0.00} on {paidOn:yyyy-MM-dd HH:mm:ss}";
Console.WriteLine(normal);
Console.WriteLine(interpolated);