im starting to learn how to interact with mysql with php. but i keep getting an error from this line of code

mysql_query(“INSERT INTO sm2lvls(‘user’,‘level’,‘rating’)VALUES($Suser,$Slevel,$Srating)”)or die(mysql_error());

the error is

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ‘‘user’,‘level’,‘rating’)VALUES(,)’ at line 1