using System;

public class Program

{

    public static void Main()

    {

        string word = "tree";

        int length = 3;

​

        // word.length is equal 4 right now

        string newWord = word.Substring(0,length);

        // new word is now a substring of word, from the start position, until the new word is of length three

        // the output here is now "tre" instead of "tree"

        Console.WriteLine(newWord);

    }

}