Combine text boxes into one string

Combine text boxes into one string

If you have two text box fields, how would you go about combing them into
one string with text in the middle.
For example
You have textbox1 and textbox2 and want to have a - in hte middle
so if the input was andy(1) maxel(2) it would come out andy-maxel
I have tried this
$daters = $_POST['11']." ". $_POST['22']." ". $_POST['33'];
$dater = $_POST['11']." - ". $_POST['22']." - ". $_POST['33'];