Mssql insert problem

I'm trying to insert a row into an mssql7 db with the following line: $query = "insert into billablehours values ($Date,$Account,$Person,$Hours)"; And I'm getting an error : Warning: MS SQL message: The name 'Mojo' is not permitted in this context. Only constants, expressions, or variables allowed here. Column names are not permitted. (severity 15) in C:\Inetpub\wwwroot\SqlAdd.php on line 23 Mojo is the value for the $Person variable which is the only varchar field and the only field I'm getting an error on (I think).Its is not the name of a field.What's wrong? The data comes from the following form: <form action="SqlAdd.php" method="post"> <p>Date <input type="text" name="Date" size="40" maxlength="80" value=""></p> <p>Account <input type="text" name="Account" size="10" maxlength="80" value=""></p> <p>Person <input type="text" name="Person" size="50" maxlength="50" value=""></p> <p>Hours <input type="text" name="Hours" size="40" maxlength="80" value=""></p> <input type="submit" value="Submit"> </form> Help and Thanks Mike P ampeloso@att.net