moving items from one listbox to another c# windows application

        List<string> list = new List<string>();

        List<string> l1 = new List<string>();

        private void Form1_Load(object sender, EventArgs e)

        {

            list.Add("hey");

            list.Add("you");

            list.Add("over");

            list.Add("there");

            listBox1.DataSource = list;

        }

        private void button1_Click(object sender, EventArgs e)

        {

            RemoveElements();

        }

        private void RemoveElements()

        {

        

            foreach (var item in listBox1.SelectedItems)

            {

                l1.Add(item.ToString());

                list.Remove(item.ToString());

            }

            listBox1.DataSource = null;

            listBox1.DataSource = list;

            listBox2.DataSource = null;

            listBox2.DataSource = l1;

        }

        private void button1_Click_1(object sender, EventArgs e)

        {

            RemoveElements();

        }