NewLine property of Environment class can be useful in giving line breaks between 2 strings.
This is shown in this example.
Take a Window application. Put 3 textboxes and one button.
We have to enter two strings in 2 textboxes and display their concatenation in the 3rd textbox
with a line break.
private void button1_Click(object s, EventArgs e)
{
string a=textBox1.Text;
string b =textBox2.Text;
textBox3.Text=a+Environment.NewLine+b;
}
Try it.