using System;
using System.Linq;
using System.Text.RegularExpressions;
 
public class Test
{
	public static void Main()
	{
		string test = "viv-ek is a good boy.Mah - esh is Cra - zy.";
        var words = 
        	Regex
        		.Matches(test, @"(?<part>\w+)(\s*-\s*(?<part>\w+))+\b")
        		.Cast<Match>()
        		.Select(
        			x => string.Join(
        				string.Empty, 
        				x.Groups["part"].Captures.Cast<Capture>().SelectMany(capture => capture.Value)))
        		.ToList();
        words.ForEach(Console.WriteLine);
	}
}

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