Help with a simple code

Hello guys, I'm new to javascript, and during my learning I came across a little problem:

Code:

<!DOCTYPE html> <html> <body> <p>Click the button to call a function with arguments</p> <form> <input type="text" id="occu" name="occupation" /><br> <input type="button" name="submit" value="Submit" /> </form> <br><br> <button type="button" onclick="MyFunction(x, 'harry')"> Click here </button> <script> var occupation = new string; var name = new string; var x=document.getElementById("occu"); function MyFunction(Occupation, Name) { window.alert("Welcome to you, " + Name + " the " + Occupation); } </script> </body> </html>

What's supposed to happen is that the user enters something in the dialog box, (lets say wizard) and then when the other button is clicked, the alert will show "Welcome to you, harry the wizard". I can't find why it won't work.

Also, if I directly add this line:
var x="wizard" it still won't work.

Thanks in advance

onclick="MyFunction(document.getElementById('occu').value, 'harry')

Thanks :)