Syntax error: "Missing ; before statement" for simple javascript

I keep getting this syntax error, "Syntax error: "Missing ; before statement 3 and 4."  Basically, I doesn't like, String Last = this.getField("Last Name");

Here is the code I have:

this.documentFileName.replace(/.pdf/,"");

String First = this.getField("First Name");

String Last = this.getField("Last Name");

String Middle = this.getField("Middle Initial");

String State = this.getField("State");

String Patient = Last + ", " + First + " " + Middle;

The goal is the code to compare the file name to the patient's name in the PDf form fields.  I haven't written the rest yet until I can get this syntax error sorted out.

Any help would be appreciated!