How to change the possessive pronoun for username?

maga

I want to change user's Activity & profile sentence... I want to apper username instead of possessive pronoun... I found that BD saved activityType

Type 1: %2$s signed in. ........ so this %2$s is possessive pronoun but where is ?

and I found in this file \applications\dashboard\settings\structure.php

// Insert some activity types
///  %1 = ActivityName
///  %2 = ActivityName Possessive: Username
///  %3 = RegardingName
///  %4 = RegardingNamePossessive: Username, his, her, your
///  %5 = Link to RegardingName's Wall
///  %6 = his/her
///  %7 = he/she
///  %8 = RouteCode & Route

if ($SQL->GetWhere('ActivityType', array('Name' => 'SignIn'))->NumRows() == 0)
   $SQL->Insert('ActivityType', array('AllowComments' => '0', 'Name' => 'SignIn', 'FullHeadline' => '%1$s joined.', 'ProfileHeadline' => '%1$s Joined.'));

I understand that if I put %2 instead of %1 appear the username, I changed the file and the BD but no appear .

if ($SQL->GetWhere('ActivityType', array('Name' => 'SignIn'))->NumRows() == 0)
   $SQL->Insert('ActivityType', array('AllowComments' => '0', 'Name' => 'SignIn', 'FullHeadline' => '%2$s joined.', 'ProfileHeadline' => '%2$s joined.'));

I changed some files .php but not....