여러 테이블을 지정하려면 어떻게 해야 할까요?

<?       $list = array();       $subject_len = 40;       $latest_skin_path = "$g4[path]/skin/latest/dada_refer";        $tmp_write_table = $g4['write_prefix'] . "talk";       $sql = "select * from $tmp_write_table where wr_is_comment=0 order by wr_hit desc limit 15";       $result = sql_query($sql);       for($i=0;$i<$row=sql_fetch_array($result);$i++){        $sql = "select * from {$g4['board_table']} where bo_table='talk'";        $board = sql_fetch($sql);
        $list[$i] = get_list($row, $board, $latest_skin_path, $subject_len);         $list[$i]['bo_table'] = $board['bo_table'];       }       ?>