How to create MDI Application in Compact framework

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace MultipleDocments_Demo
{
    public partial class mainscreen : Form
    {
        MotherClass mc;
        public mainscreen(MotherClass mcTemp)
        {
            InitializeComponent();
            mc = mcTemp;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            if (mc.f1 == null)
            {
                mc.f1 = new Form1(this.mc);
            }
            mc.f1.Show();
        }

        private void button2_Click(object sender, EventArgs e)
        {
            if (mc.f2 == null)
            {
                mc.f2 = new Form2(this.mc);
            }
            mc.f2.Show();
        }

        private void button3_Click(object sender, EventArgs e)
        {
            if (mc.f3 == null)
            {
                mc.f3 = new Form3(this.mc);
            }
            mc.f3.Show();
        }
    }
}