Namespace Error

[Memnoch1207]

I am receiving this error:

The type or namespace name 'debug' could not be found (are you missing a using directive or an assembly reference?)

here is my code:

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Data.SqlClient;
using System.Diagnostics;

private void Form1_Load(object sender, System.EventArgs e)
		{
			SqlConnection conn = new SqlConnection("Data Source=webappserver; Integrated Security=SSPI; Initial Catalog=pubs");
			SqlCommand  cmd = new SqlCommand("SELECT * FROM jobs ORDER BY job_desc", conn);
			try
			{    	
				conn.Open();
		
				SqlDataReader myReader = cmd.ExecuteReader();
	
				while (myReader.Read())
				{
					cbo1.Items.Add(myReader["job_desc"]);
				}
				
				myReader.Close();
				conn.Close();
			}
			catch(Exception)
			{
				
			}    
		}

		private void cbo1_SelectedIndexChanged(object sender, System.EventArgs e)
		{
			debug.write(sender, e);
		}

anyone know why I am receiving this error, even though I am using the System.Diagnostics namespace? I'm using 1.1 framework.